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Replacing the coolant crossover pipe

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02-20-2009, 03:29 PM
Anyone have any tips for disassemling and replacing the gaskets on the coolant crossover pipe. This is the pipe that is at the rear of the engine and supplies coolant from one head to aother on the 3.5L engine.

Any tricks, tips, shortcuts or instructions you would care to supply would be appreciated. I'll be doing this over the weekend I hope.

02-21-2009, 09:46 PM

I've never done this repair, but I have a 2000 Intrigue with the 3.5L that is using coolant, and has dried coolant on the bolts on this crossover.

I've reviewed the information on AllData for this repair, and it doesn't give a procedure.

It would be kind of understandable if the exhaust manifold wasn't right in the way. I'm wondering if it would be accessable with the intake manifold pulled off, would that give access to all the bolts on the crossover?

Maybe the bolts could be removed without pulling a lot of other parts off, but it doesn't look like there's a lot of clearance if those bolts are over a few inches long..

I found someone on another forum that mentioned he did this, but his post was from 2006, and he hasn't returned an e-mail.

Anyone out there got any ideas for the water crossover near the exhaust manifold on the drivers side of the engine?

Please keep us updated or send me a PM if you want to chat about this. Felpro makes the gaskets, but it looks like it could be a pretty extensive job.

12-04-2009, 08:40 AM

12-04-2009, 09:14 AM

The gaskets can be found cheaper than $12.00 a piece at the problem becomes the labor. I don't know how much is involved with loosening the rear exhaust manifold with the engine in it's current position in the car.

Didn't you just put this engine in your Intrigue, or based on your shutterfly site have you picked up another one? If this is on the car with the new water pump it looks like that was leaking for quite a while, based on the corrosion.

Anyway-- Drop me a PM with your E-Mail address if you need any procedures and i can look over the holidays. If I remember right this procedure isn't in the Alldata for Intrigues, but it is in AllData for the Aurora 3.5L, and there's a few people over at Aurora Club of North America that have done this.

You've pulled an engine, so I'm sure you can do it.. The question is how to get at it without moving motor mounts ect..

12-04-2009, 11:25 AM
I ended up doing this job aboy 3-4 weeks ago. I typed up a detailed rply on this site but when I submitted it I guess my login had timed out or something. It said I needed to login even though it said "Welcome slb04786" in the upper right hand corner. After logging in it said my reply coudn't be posted because I had logged in and to click on the back button to go back. Doing that took me to a blank reply. I had spent about an hour explaining what i had done and it was all gone. Should have used the copy function first I guess. I was so disappointed I didn't feel like retyping all that again.

Basically, yes you need to loosen the exhaust crossover pipe. I only loosened it on one side as I couldnt get to the backside. All but 1-2 of the coolant crossover bolts will come out with the exhaust pipe there. i used a prybar to move the pipe just enough to allow the other 2 bolts to come out. It only need to move 1/4-3/8 inch. I'll try this reply and hopefully it will go through.

12-04-2009, 11:32 AM

So you only removed the two bolt's where the rear manifold flanges to the central pipe, not off the exhaust ports itself?

Prybar-- So there was enough flex in the exhaust pipe, or did "Strategic Denting" with the crow bar allow you to gain the 1/4-3/8" needed.

Mom's car has suprisingly stopped eating the antifreeze, but now it's using a quart every 1200-1500 miles. I haven't done this repair, but it's only at 75,000 miles for a 2000. If I keep it, this job probably will be in order.

Thanks for the update..


12-04-2009, 11:51 AM
Yes, I just removed the 2 bolts on the flange. I did'nt need to do any denting of the exhaust pipe. Removing those two bolts allowed me to put my pry bar (crow bar) down between the head and the pipe and move it just enough to loosen the other 2 coolant crossover bolts and lift it up and out with the bolts. It's tight but I had just enough movement to get the job done. Much longer bolts and I wouldn't have been able to. I couldn't even get to the exhaust bolts on the other side of the engine. I couldn't even see if there was a flange down there or not.

I hope this helps. Let me know if I can offer anything else.
1) I removed the EGR valve to get room to work on that side of the coolant pipe bolts
2) Once I had the pipe loose I removed the engine mount/stabilizer (my own word) plate to get more room to work on that side.
3) I used a gasket shellac to help hold the gaskets in place during reassembly. I don't know if it is recommended or not. I haven't had any problems with leaks yet. Knock on head.
good luck

call me if you need immediate response. My cell phone number is on my website

12-04-2009, 01:53 PM

12-04-2009, 02:10 PM

12-04-2009, 02:45 PM
Thanks, I think. Ya, I'm definately "Shade Tree Mechanic". Only my shop is not as spotless as theirs was. Haha.

Once I unbolted the flange I could move it just enough. Didn't have to move much.

Looking at your picture reminded me that you will need to unhook the EGR and the flex pipe below it as well as the heater hose that are on the crossover pipe. It's nice to see why I couldn't find a flange on that side of the engine. No way I could have unbolted the manifold on that side.

12-04-2009, 03:23 PM
Good luck krivasauto-- I learn something every time I log in here. I believe the EBCM may require programming to the vehicle. I remember a post mentioning a company that can rebuild the electronics of this Bosch Module, but if I remember it was a few hundred dollars. Anyway that's another discussion. For another thread.

It's becoming snowy winter here in Minnesota so most of my projects will be on hold until spring, but always willing to throw around idea's..

12-04-2009, 04:00 PM
Looking at your picture reminded me that you will need to unhook the EGR and the flex pipe below it as well as the heater hose that are on the crossover pipe. It's nice to see why I couldn't find a flange on that side of the engine. No way I could have unbolted the manifold on that side.

I have read that you are supposed to replace that EGR pipe if you remove it - I assume you have no exhaust leaks?

Here is a picture that will help others visualize what we are looking at. This view is if you were standing in front of the car, looking back toward the driver's side rear of the engine compartment: vPhI/cC/f%3D0/ps%3D50/r%3D0/rx%3D720/ry%3D480/

12-05-2009, 06:05 PM
According to the 3.5L 2001 Aurora procedure both the EGR inlet and outlet pipes (Both of the flexible lines that attach to the coolant crossover) have a crush connection on the end that attaches to the Water Crossover. Inorder to reuse the hoses the procedure recommends not to remove the connections to the water crossover. Remove the other ends. This of course doesn't make using the crow bar trick any easier with this stuff attached.

It's funny that the Intrigue shows 6.5 hours of labor for this job, but with no procedure. But the Aurora mentions the procedure of removing the right manifold exhaust manifold. But both the Intrigue and Aurora procedures for the right manifold require near engine removal! So this will be a great trick and it sounds like it might work!

12-06-2009, 09:53 AM

12-06-2009, 06:33 PM
According to the following links over at the Aurora forum it looks like they removed the throttle body, and heated the bolt on the rear exhaust manifold and disconnected the EGR Inlet from there. It also appears to mention that they went after the rear exhaust manifold with a series of extensions, Maybe from the top? ( ( (

12-07-2009, 06:59 AM

12-08-2009, 07:07 PM
Stan -
I too, wish you hadn't lost the writeup you worked on. My 2000 GLS may need this work done on it when warm weather returns next Spring. As someone else said, this thread is collecting some good info.
It is maddening to find yourself "logged out" without any warning, and your writeup lost. I learned to copy everything -- often -- to the clipboard while writing a post, and then save the clipboard contents often, to a text document on my desktop, just in case you need to be able to copy it back quick, after a surprise logout. At least you don't have to recreate it all.

12-11-2009, 07:13 PM

I noticed that you revised one of your pictures on 12-11-09 as to where to pry with the crowbar. Were you able to do it without loosening the rear exhaust manifold?

I know your probably working on it now, and you'll update us when you have a chance.

My 2000 Intrigue had a puddle under the drivers side last night. Only seems to leak when it's really cold outside. I haven't confirmed 100% that it's the crossover, but there appears to be dried coolant on the bolt heads. Any interest in seeing a white Chistmas in Snowy Minnesota? I might have to figure out how to get this to go till spring or park it till then.

Best of luck from all of us that are still following this. Nice start on the EBTCM as well.


12-11-2009, 11:00 PM

12-14-2009, 10:42 AM
Hey Guys-

The cold weather has caused my 2000 to leak, and I've been calling around for quotes if this is the issue. (I'll discuss that leak and location with pictures in a separate post. )

I called a former Oldsmobile dealer, probably the largest in the Twin Cities area and spoke to a tech/service adviser. He mentioned having to remove the entire intake manifold. I mentioned does the rear exhaust manifold need to be loosened/touched and he said no. The only thing I can think of by pulling the intake manifold would you have enough room to remove all the bolts except the "middle bottom" and then rotate the cross over enough to slip new gaskets in there? Maybe the cross over really doesn't have to come completely out from under the big exhaust pipe? I thought I'd throw that out there.

12-14-2009, 11:12 AM

12-15-2009, 06:44 PM
Hello all,

It is stunningly amazing that I hit upon this thread at this time. Just a week or two ago I didn't hit anything close on Google about changing the crossover seals.

I am an owner of a 1999 olds Intrigue with the same problem this post is discussing. I am planning on fixing the leak probably around the holidays. I have bought all the seals, including the exhaust manifold set because that is what I assumed needed to be done (remove the right exhaust manifold). I wait with great anticipation as to if using a pry-bar really works to make this repair go easier.

I did spend a little time under the car with extensions and ball-swivel adapters to see if I could get a 13mm socket on all the manifold bolts (6). And basically concluded that I could if the exhaust pipe to the catalytic converter is removed. but if I don't have to remove it that would be awesome.

thanks to all for your input.

12-16-2009, 07:18 AM

12-17-2009, 10:43 AM
My apologies to Stan. And thank you Krivasauto for correcting me.

I will give this method a try, but if while pulling on a crow-bar I get the feeling like I am breaking something, I will stop and go the longer route by removing the manifold.

Maybe will start this weekend and try to finish before the holidays.

later, Steve

12-17-2009, 12:46 PM

12-21-2009, 10:34 AM
Krivasauto and others,

Just wanted to get off a quick post about how the job went, will offer a more detailed post possibly this evening. Big questions, ANY LEAKS?... none. Did I try prying the right manifold (RM) crossover?...yes, but it didn't move enough to be of any benefit, so ended up removing the RM anyway. How many hours?...about 14 hours.

I will explain further why it took so long, but basically I'm a slow mechanic who takes my time to make absolutely sure I don't mess anything up, 'cause I don't want to have to do it again.

Why the prybar trick didn't work? The left manifold (LM) extends up into the RM about an inch. So after I did remove the RM I relized why I could only pry about 1/4inch easily then hit a stop. I was hitting the LM. Was 1/4" enough to get the crossover off? maybe if I had another arm (pulling the prybar at the same time I am pushing on a wrench). On my car there is only 3/16 inch clearance between the top of the problem bolt (center bottom) and the RM crossover. And the bigger issue is the engagement of the bolts into the heads is about 3/4-7/8 inches!!! It would have been impossible for me to make the prybar trick work.

I will write more later, and will offer tips also. Like, when removing the two exhaust nuts (RM to pipe) use a 1/2" (SAE) socket with a 1/2" drive. the 1/2" socket is a little snug on the 13mm nuts but it worked excellent, especially after I split my Craftsman 13mm deep-well 3/8" drive socket. I used a standard height socket from a more robust manufacture than Craftsman.

later, Steve

12-21-2009, 12:22 PM

12-21-2009, 10:29 PM
Krivasauto and others,

I’d like to offer a reason for the long time (14 hours), some observations of the whole job, and finally some tips that I did or should have done.

Why did it take me so long? I am a very methodical person, who does things step-by-step. By profession I am a mechanical design engineer, specializing in high-speed rotating machinery typically for aerospace applications (over 31 years experience, thus you can figure about how old I am). Am I a “gearhead”? No, but I would rather be tinkering in the garage with the stereo on, changing the oil on a car before participating in “house-cleaning day” with the Misses. This was definitely the biggest repair I’ve done in a long time, as the last big repair I did was rebuild a TurboHydramatic tranny with the help a friend. Mostly I just do oil-changes, plugs, and brakes on my vehicles. I was a little worried about this project.

So why did it take me so long? As I said in the previous post I did not want to make a mistake. I do such things as wire brush all the bolts that have corrosion damage, and carefully scrape the old gaskets off (see below trick that I used), and as I remove stuff I carefully organize it on the garage floor (with its respective fasteners) in the order I removed it (so I know how to put it back on). And if a lousy song shuffles up on the iPod playing over the garage speakers, I don’t hesitate to get up and hit the skip button.

Before I took on this job I did buy a complete set of official shop manuals I found on Amazon. They were used and I got them for about $65. I already had the Chilton manual I bought from the local auto parts store but obviously it didn’t discuss the crossover manifold. The manuals proved to be a very good reference for me. The Fel-Pro gaskets I ordered are (all from Kragen Auto parts):
#35722 (qty 3), crossover manifold (3X $7.00)
#70788, EGR ($2.49)
#61304, Throttle body (paper) ($.99)
#61305, Throttle plate (molded rubber) ($2.49)
#MS96346, Exhaust manifold SET (left, right, crossover donut, and the EGR oring for the pipe going back into the intake manifold) ($22.00)
#61310, Exhaust pipe ($7.50)

Is this a complicated repair? Not really, when you think about it there is really only a handful of fasteners and about 5 things to remove (exhaust-12 fasteners total, throttle body/intake-9, crossover/EGR stuff-14, engine cover-2, water hoses-3, and a few electrical plugs-7). But honestly, the exhaust removal and assembly took about 7 hours on its own (2.5 hours to remove and 4.5 to put back on).

I started by removing the obvious stuff on top: negative battery terminal, intake duct, linkage from the throttle body, engine stabilizer, drain the coolant, throttle body (3 nuts), then the throttle body plate (three studs using a 5mm socket, and the little screw hidden under the paper throttle body gasket). I only took one of the little hoses off the throttle plate, leaving the smaller hose attached between the crossover manifold and the throttle plate. I did this solely thinking that the less hoses removed the better chance I won’t have a leak. Removed the other two hoses (to radiator and heater). The heater hose I ended just cutting off, as there was still enough length to be able to reattach.

Tried the pry-bar trick, but as mentioned above it didn’t do the trick for me. And realizing that I wanted room to properly clean the sealing surface, and to be able to get my hands in there, I decided to remove the right manifold (RM).

From underneath began removing the 3 foot pipe attached to the RM, using penetrating oil and the ½” drive sockets (1/2” SAE). I did not remove any O2 sensors, only disconnected the one connector. The hardest fasteners to remove on the hole job were the two nuts between the pipe and the RM. The manifold was easy to remove the 6 bolts. you will need to remove the tranny dip-stick pipe (one screw) but have a container ready to catch about a pint of tranny fluid (I wasn't ready!).

The crossover bolts were difficult as on one of them (lower left) I almost rounded the head. Hindsight I wish I had used a ½ SAE socket instead of the 13mm, as it probably would have gripped the bolt better. Two of the bolts were heavily corroded from the leaking fluid. The seals literally crumbled into pieces. Then put it all back together.

The most difficult part in putting everything back on was the RM. First put the donut on the LM pipe, position the RM on the LM pipe, and crawl under the car for a couple of hours trying carefully to finger-thread the 6 bolts in. I believe I may have cross-threaded possibly 2 of the lower bolts, but literally gave up trying to get the bolts in. If you have smaller hands and arms it should be much easier for you. Try your hardest not to drop the bolts as some will fall to the ground but I had one fall between the transmission and the engine and could not retrieve it. Luckily my local hardware store had one! When putting the RM back on you will want to work slow and carefully. The three top bolts are easiest, but the bottoms are the hardest. I used about 20" of extensions for all these bolts, and as long as you had wobble ends you can get to all 6. Everything finally torqued down OK.

My tips:
1. Use Anti-sieze on all the fasteners.
2. Use GM sealant ($17, requiring a caulking gun) on all coolant gasket surfaces.
3. I used an electric Palm sander on several sealing surfaces to clean them up. This is a wonderful trick I’ve done many times in the past.
4. I used a Come-along to pull the engine forward, to facilitate access to the RM bolts. Tied one end to a stud in the garage, the other to a crow-bar wedged in the motor stabilizing bracketry. Ust be careful you don’t pull too much as to flip the car off any jack-stands.
5. As discussed earlier, a ½” socket may work better on difficult 13mm bolts.
6. I used several Wobble extensions, and a wobble impact “Ball” adapter (Craftsman 3/8” drive)
7. You will need a little mirror to find bolts you dropped.
8. And get one of those little grabber gizmos (about 2 feet long) that has the little metal prongs that flair out.
9. Jack-stands for the whole car (4). Be careful!!!!
10. Manuals I found very useful
11. And most importantly, a Radio playing your favorite music.

I want to discuss one more topic… Sealing. I generally put either GM Sealant (the best), or Permatex sealant (I think either 2A or 2B? the black one) on all seals for coolant, trannies, oil pans. Years ago a mechanic told me you never have to put goop on gaskets as long as you torque them correctly. But I use sealant (goop), and have never had a leak. Someone may say, I don’t need to put sealant on the crossover seals as they have built-in rubber gaskets. I would rather put the sealant on the mating surfaces and be safe, than to put everything together (14 hours) and discover a little weeping leak.

That’s my experience. I may have left something out, please feel free to contact me with any questions. Sorry I didn’t take pictures, but my hands were dirty and it would have added another hour to my effort. Hey it took me over an hour to write this!!!

Let me know how your crossover repair goes, and good luck and be careful when under the vehicle. Steve

12-22-2009, 07:23 AM

Thanks for your additional comments on this. It gives me the idea that without help, I don't know if I'm going to tackle this project. That rear manifold being under the car would drive me crazy!

I'm glad your Intrigue's back up and running.

I'll be following this discussion even if I don't do this till spring. Still debating what to do with the 2000 Intrigue.

Happy Holidays to everyone.


01-04-2010, 04:02 PM

01-04-2010, 04:32 PM

Sorry to hear about that headgasket, and just thinking of the work you'll have ahead of you now is amazing.

I haven't done anything with our 2000 coolant leak either. It's still external, but fairly slow to nothing if you don't use the heat of the car. Using the heat hard causes more coolant to leak. Don't quite understand why, as you would think that cooling the engine by using the heater would decrease pressure. No leaks inside car, or film on the windows. Pretty sure it's not the heater core.

Anyway-- Sorry to hear about that headgasket, at least you have experience pulling the engine. Maybe the front head could be pulled with the engine in the car, but I'd think working on the timing chains would be difficult.

I'll keep watching your shutterfly site for details.

01-04-2010, 11:01 PM
I'm taking my 2000 Intrigue in for an external coolant leak that I've had for a while. I see coolant on the ground (centered left-to-right and ~3/4 forward in the engine compartment). I lose about a liter / 600-700 mi. I tried to have this fixed last year, but the shop incorrectly diagnosed this as a leak at the thermostat - new tstat didn't fix it. From what I've read, I suspect my problem is the coolant crossover pipe and am preparing for a big labor bill. If it is, I'll try to find out how they access it and post back.

01-05-2010, 04:44 PM
Krivasauto and other "Intriguer's" with coolant leaks,

I didn't want to scare you away from this repair by stating that it took me 14 hours. Looking back could I have done it quicker? Yeah, I probably could have done it in 6 hours had I not lost one of the RM bolts, and not fussed with being so meticulous. If you've got recent experience with swapping the whole engine, I am sure you have the skills to do it within 6 hours also.

later, Steve

PS. It's been awhile since I did the repair. Not a drop of coolant lost!
PPS. Bummer about the head gasket! may end up changing the crossover gaskets anyway.

01-12-2010, 12:10 PM

01-14-2010, 07:30 PM
It did end up being the coolant crossover pipe. 6 hrs of labor to remove right exhaust manifold, egr valve, throttle valve. GM certainly could have done a better job on designing this one.

01-14-2010, 09:09 PM
GM certainly could have done a better job on designing this one.
I'm curious - how many miles on your engine? Do you know what the coolant service history has been? How do you know the supplier of the gaskets didn't let GM down?

01-14-2010, 09:48 PM
I have 67K on the car ('00). I changed the original coolant after 8 years and at about 55K. I had meant that the design could have been better thought out to allow access to the pipe by flexing, rather than removing, the manifold. But, the design of the coolant pipe connections could apparently have been better too since they all seem to leak after 8-10 years. There very well may have been problems with the gasket supplier, but with this problem being so pervasive to Intrigues, it does not seem that there was an isolated vintage or batch of inferior gaskets. I'm also willing to bet that the gasket today is the same as it was 10 years ago and will leak again - I'll let you know in another 10yrs :)

01-15-2010, 09:23 AM
I've got a '99, 3.5L, and about 90K miles. Still no drips sinse repair. I totally agree that the design could have been thought out a little better.

02-17-2010, 08:07 PM
Hope this thread isn't too old. Looking at this repair - my '99 Intrigue leaving puddles on the floor, not sure if it's this or head gasket (how do you tell?). Just wondering, seems like the RM has to come off to clear two bolts. Could these be backed out and cut off, and the replacements be cut down 1/8" to 1/4" yet still have enough engagement to make a good seal, or is this just making it harder?

02-18-2010, 09:42 AM

No, this issue is still fresh in my mind. To find the pjroblem I looked real close with mirrors and lights into the area around the two locations where the crossover attaches, and found weepage in the location. I even carefully hosed the area down and re-checked the next day to be sure I would find fresh coolant.

In my opinion, you are going to want to make sure the job is done properly to insure you never have this problem again. And even though it was a big effort on my part, I am glad I had the extra room to get my hands in there to properly clean and prep the mounting surface.

In my earlier post I said it took me something like 14 hours. But like I discussed in a follow-up post, hindsight I am sure I could have done it in 7, maybe 6 hours. But I was just being too cautious.

Keep us posted, and good luck,

02-18-2010, 11:27 AM

02-18-2010, 01:47 PM
Go to ! Has lots of info on the procedure . Good luck !

02-18-2010, 03:24 PM

02-18-2010, 03:34 PM
Sorry , didn't mean to " step on your toes " !

02-20-2010, 12:26 PM
krivasauto, suburbanstevie, Thanks for the advice ('though I had to look up 'panoply'! these forums are more educational than I realized). I was afraid this would be the answer. Probably doubles the time. That pictorial is very nice, should be quite helpful to any shadetree attempting this job. Trying to be rational here. The car is still nice, but $leak, $wheel bearing, $AC leak - I think it's almost totalled, unless I use sweat equity, but I think I'm going to have to ask for help on this one. Fortunately, for now, antifreeze and water are cheap.

08-25-2011, 08:29 PM
The pry bar shortcut worked well after removing throttle body and adapter and left manifold, I removed radiator fans to make that a bit easier, but could probably have done it without that. Was much easier than removing right exhaust manifold. Another pair of helping hands while prying is recommended.

08-26-2011, 09:52 AM

Very clever solution. I never thought of that approach. Curious... how many hours for the whole job?


08-27-2011, 04:01 PM

11-15-2011, 06:43 PM
Make sure all the bolts are off on the EGR valve near the cooling fan and pulled away, there is a 15mm bolt also holding the EGR tube running parallel with exhaust manifold. slip the crook end of crowbar underneath exhaust manifold and EGR tube, with some wrangling a spot should be found to pull the manifold out, up and away just enough to slip out the Crossover pipe. I used a 1/4" flex-extension with 13mm end to get out difficult bolt. The Crossover manifold uses 3 identical gaskets with metal grommets or spacers and it seems to me that the metal spacers prevent the gaskets from sealing completely and a blown seal is inevitable. Removal of the intake manifold and throttle body is pretty much a given. When removing the Fuel Injector connectors it is not necessary to remove the blue locking clip entirely, instead remove it half-way one click and use small screwdriver to push black tab back then gently remove the connector.

11-16-2011, 09:40 AM
The metal grommets on the three gaskets are there to make sure you don't over-tighten the seal. the seal is designed to provide the correct amount of "squeeze" on the gasket's rubber to seal properly. What is important is to make sure the surfaces are smooth and clean.

09-18-2012, 03:38 PM
My question is: Is this the solution to the persistent problem of flow, no internal heat at idle,overheating at idle, highway speed (55/60mph) it the engine cools and internal heat is great, then at highway speed gets hot again after awhile, and will cool to normal once revved over 2000rpm. I'm guessing due to release of pressure/water from these gaskets and the seemingly unique and delicate cooling systems of the 3.5 Intrigue?
Actually hoping this is the solution:crying:
I know that I will have to replace these cause I have spotted the seeping at the top of left/front gasket. Just hoping that this will resolve the above issues.....?
Currently own 2 2000 Intrigues, one a GL the other the standard 4 door. Both have these symptoms, one has been traced to the seeping gasket.

09-18-2012, 03:47 PM
Both Intrigues have been sold over a year ago, but this thread in my inbox made me post. I still have a soft spot in my heart for the Intrigue!

Anyway to the question- The 2002 Intrigue that I had did suffer from having a difficulty getting air out of the coolant system. It takes a lot of time to bleed it. If your not dealing with air in the cooling system, and it's operating ok then I'd leave it.

The 2000 Intrigue was leaking at the front of the crossover manifold.. Dripping near the front headgasket. While it was always drivable, and didn't overheat the coolant leakage became quite noticable. More so when the engine was operated in winter ambient temperatures.

I sold it to a local dealer with this issue, along with the transmission PCS issue. Do some googling on for 99Intrigue.. He used to post here under the handle KrivasAuto. He had some good pictures of what's involved.

I had difficulty finding a shop that was aware of the LX5 3.5L Engine, and this issue, and was quoted nearly $1500 for the repair. I latter found an old Oldsmobile dealer who knew the issue and would do it for around $700, but I never did.

Good Luck--

09-18-2012, 04:08 PM
Yes, had air bleed issues. Took several attempts and lots of patience. Finally after several times of it back filling and bubbling through the hose at the bottom of resevior bottle and out the over fill tube, the air is out, it seems to come to full pressure and temp like normal but the flow problem seems to be my issue, mainly it seems at the heater core, until it gets a rev of rpms then all returns to normal...

09-18-2012, 04:14 PM
And you opened the black plastic bleed valve on the top passenger side of the radiator?

Also remove the two screws on the radiator tank and lift that up, with the cap slightly open lift the entire tank. Don't disconnect the hose to the thermostat housing. Tie this bottle up in the air to the top of the hood. Let it sit with the bleed valve on the radiator open.

You have air in the system. It's possible that those gaskets could be pulling in air, or something, but you shouldn't have that bad of flow problems.

No misfires, or potential concerns with the headgasket?

I think you still have problems with Air. I spent $100 and bought an Airlift coolant system evacutator. I was so fed up with the problem. Until I learned that lifting the coolant reservoir off the back firewall is not that hard. (Did that for a power steering pump removal.)

09-18-2012, 04:35 PM
I'm with carbon2 on this. The leak will not cause loss of circulation but air in the head or pump would cause it. If you have had to add coolant a few times because of it being out or extremely low then I think that is you problem. Try what carbon2 recommends by lifting the coolant tank above the radiator and keep the tank full with the bleeder open on the radiator.

12-24-2012, 02:37 PM
What is the name of the gaskets that are on the coolant crossover pipe????

12-25-2012, 02:03 PM
Nevermind i found out thanks for the tips on how to replace and merry Christmas!!!

01-05-2015, 11:20 AM
thanks stan for starting this post and for the pointers on the telephone a few days ago! very kind of you to take that extra time on the phone and it

was comforting to hear the words from the person who started this thread!

i know he has his fixed and sold, but it helped us SO much, i wanted to contribute my thoughts and how i repaired the wifes car. hoping this will help others who try the "CROW BAR TRICK".

thanks to the rest that contributed as well! it all adds up and helps paint a picture, at least, for those who might want to try to take this thing on. i would NOT want to do this again! it was very hard on my back and neck and ended up laying on the car for some reprieve, when ever i could. it took me 6 hours to take it apart and another 6 to put it all together. both times out side in freezing temps and blowing winds and snowing hard. was 32 degrees both days. i did buy a swivel gear wrench in size 1/2" as thats what the wcp bolts use. odd thing tho, putting it back together is wanted 13mm on some of them. after reading over this thread a few times i decided to try to fix my wifes olds with exact problem on exact engine. i did it differently and left the intake intact and the water cross over pipe in place. i just removed the egr so i could turn the pipe and the water out let pipe on the rear of the water cross over pipe (WCP) and the 6 bolts, three being shorter than the other three. those are easy to figure where they belong.

i think the trick was to pry the exhaust pipe up high and back enough to allow access to all 6 bolts. altho with the worst of them in the rear two bolts. used a crows foot to do a lot of the turning after they were loose. used it also to break loose the bottom rear bolt. used to hand tighten both back up also. i did break the water temp sensor not knowing i did so. so it broke super easy. never heard it or felt it go, so be careful. i needed to replace it any way and tried to do that a week or so before doing this job on it. so it was a win win. being broken made it easy for a 19mm socket to fit it to get it out. the manifold looked like a pain to remove, so i looked for another way and decided leave it there and clean it and and the heads (scraper and gasrag) and spray high temp gasket adhesive/sealant to the gaskets and the cwp the best i could. the gasket holes are very tight on the bolt and i think they were made that way on purpose to help keep them in place. a bonus if you will, but also a curse trying to do it with only two hands and in place. the hardest gasket is the rear. just get the top bolt in first, then the bottom. it will hold the bolts from slipping out so you can do the fronts next. i did add high temp atv silicon to the bolt shafts making a spiral from threads to head.the front four bold and gaskets are super easy to work with. just the rear is a real bear! one of those things you wish you could farm out.
the trick to getting this whole job done was to use several crow bars and the transmission. the tranny has a flat right on top and just under the exhaust cross over pipe (ECP) that i usedto raise the ecp many times. i would use one bar to lift and then shove another bar under it and continue this until the ecp came up and over the raised 1 1/2" extension pipe that extends from the manifold (reverse this to get it back down after the rest is assembled), but this also raises the pipe in the rear, so while you are able to get a wrench on the top rear bolt, try to see when you can break it loose, before the pipe gets too high and in the way. then you are good to go to slip the pipe over that extension pipe. this allows you to turn the wcp and clean it the best you can and spray it with sealant/adhesive. i did remove the rubber hose that goes to it so i could move the wcp back and forth to get more clearance/angles.
once assembled the exhaust pipe did now want to return to its original place. so i used the 4 foot crow bar (used it the most in the entire job) to hook into the tranny bolt area and wedge the bar on top of the flange of the pipe and down and over to align the bolts and did that standing in front of the car so i could manipulate the parts. i did the front bolt first by hand and the rear one next. i was able to tighten them from the same place using a deep wall 1/4 socket and ratchet.
i did use the 1/4" drive on the rear bolts too to tighten the bottom rear because its the narrowest to use. i also use warble extensions (you need several lengths to get it right because the tranny shift bracket is in the way too. used a 4" i think it was. could go out to measure it. you can not get a straight line to these rear bolts and only two in the front get a straight line to them.i did use the crows foot to break that rear bottom bold loose tho on the 3/8" warble extension and then was able to use my hand to remove the bolt. when putting that bolt in, you have to get it started while the ecp is at the furthest point up and away (i used a exhaust pipe bolt to keep the ecp pipe from slipping off the raised manifold pipe for safety) and get them all started except he rear top has no real clearance to hand start. so you have to pull the safety bolt and start walking the ecp pipe back down to get the rear top to be able to start. to get the heater hose off the rear tube, i used a razor knife and cut a short slit from the top down about one inch, knowing i can cut it square latter to reassemble it.

the main key is to be able to walk the pipe up and down when needed. i also used a mason hammer at certain points to hold the ecp at a certain height. the square end of it is a perfect shim when walking the pipe back down at times.

when i spoke to stan on the phone he mentioned cutting some bolts down to make them easier to fit. i was ok w/o cutting any until i went to bolt on the front motor mount that bolts to the side of the engine. i forgot to put it back on before the ecp. so the top bolt was about 3/4" too long (hits the goose neck) to reuse and i was NOT going to remove the ecp to install it first, so i cut it with a saws all and it worked out just fine. after deciding to leave the cwp in place to change out the gaskets, the front motor mount did not have to come off any way.
if you think your back can take 12 hours leaning and this job testing you will and patience, then you have the info to be able to do it. would be best served up in summer time and with zero pressure to get it done. i had a time factor to get it done because of working in the weather. today is minus 20 degree winds and i wasn't going to be working on it in those temps. all week long is supposed to be like that. so yesterday 12/04/14 was my last day. the wife kept saying quit and finish later, but i knew there was no later any time soon.

the gaskets are;
fel-pro 35722 water out let. you need to buy 3 of these. i paid 6$ each.
fel-pro 70788 egr gasket. i paid 1.94$

one other note, when i was starting to take off the manifold, i took out the egr tube and it was plugged almost. had a tiny hole left to breath thru.

the car has 250K miles in it and a lot of wet suit from by pass gas from oil maybe. no smoke comes out of the exhaust pipe tho, but we have to add once and a while between oil changes. also the o-ring gasket on the end of that tube was in bad shape and i bought the intake mainifold gasket
kit. was 6$ for those and came with the egr gasket. so it depends on if you want to replace that gasket if you want this gasket kit. if so then omit the egr gasket i mentioned above. you don't need two of them.
thats a fel-pro ms96359 intake manifold kit. looking at the box, it gives part #'s for each type, so the pipe o-ring # is 95768.
also, had to clean all the suit/by pass gas debris off the back of the tbi. used a can of carb cleaner and a tooth brush. was caked on heavy like the inside of the manifold is too. best to clean out that tube at least. it was hardened suit. i used a needle nose pliers to break it up with the tip and then the side of jaw to cut into the suit on side of the pipe deeper in.
used pb blaster on the exhaust bolts and a 1/2" impact from the underside to get them out. came out easy like that.

so good luck to those who are unfortunate enough to need this topic here. it is do-able, but no fun at all. saved us up to 1500$ , so was worth it.

hope you are inside or doing it in warmer conditions!

01-05-2015, 02:28 PM
thanks stan for starting this post and for the pointers on the telephone a few days ago! very kind of you to take that extra time on the phone and it


I received a message today in my e-mail account from this post. It's been a little over three years since I've sold both Intrigues and in a way I still miss the big GM comfort.

However, I don't miss dealing with the LX5 Engine design. I'm glad it worked out for you, you were braver than I would ever be.

I now own a Cruze 1.4L 4 cylinder. To hear people complain about engine access to this 4 cylinder makes me laugh. Nothing like the larger V6 DOHC GM designs like the LX5.

Anyway happy new year to anyone that I used to work with LittleHoov and Panzer Dragon.

I still have OEM spark plugs and a 4T65 Shift kit for this transmission that was never installed. PM me if interested.

Take care Intriger's. I miss it, and I miss it even more at gas under $2.00!

01-05-2015, 07:09 PM
3300, thank you for the kind words. It was my pleasure to interact with you on the phone and share my thoughts on my repair. I posted the original article in hopes of helping someone else. I did not realize how many people would come to reference it in their own repair. I have received numerous emails and phone calls about my post. Thank you to all who have also shared their experiences with this repair. It definitely isn't for the faint of heart. Keep posting guys!

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