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Coolant smell, but no visible leak.

09-08-2009, 11:45 AM
However, I sense there is one because the reservoir doesn't remain full after a week or two of driving. In one incident I saw smoke coming out of left driver side of the engine, but only for a few seconds. I pulled over and saw no visible leak of any kind, the engine wasn't overheating, the fans were on, and the reservoir was just below full with the hoses running full and hot. Any ideas?

09-08-2009, 11:54 AM
Year, engine, and mileage would help but I think based on the info you gave a fair hypothesis is you have the ever popular leaking Intake Gaskets.

09-08-2009, 12:10 PM
oops sorry - Malibu 99 3.1L 140k

09-08-2009, 12:21 PM
Lower intake gasket, Almost 100% guaranteed! If you look under the throttle body you can sometimes see a build up of coolant or at least some signs of coolant leaking. This is the normal first place for the leaks to show up.

09-08-2009, 12:40 PM
Lower intake gasket, Almost 100% guaranteed! If you look under the throttle body you can sometimes see a build up of coolant or at least some signs of coolant leaking. This is the normal first place for the leaks to show up.

Thank you for the quick reply. Any idea how much replacing that would cost? Also, I wonder if this could somehow affect engine temp?

09-08-2009, 01:19 PM
If your low on coolant absolutely!

You can expect $500 to $1000 depending on your market and what exactly is done. Its not bad idea to replace the oil pump drive o-ring which is probably leaking oil, the thermostat, a lot easier to do with the lower intake on the bench, Spark plugs if needed, way easier to change the back three with the intake off.

09-12-2009, 01:15 PM
quick update - I checked in with Strauss in my area and they don't do that job on Malibus anymore because, apparently, they didn't do a good job on another malibu which caused it to catch fire. So they are out.

Pep Boys gave me a detailed quote that was just under $1000 ($956), which includes a charge for a complete coolant exchange, oil change, disposal fee's, and a A/C power sterring interferance charge.

Firestone told me over the phone $500+ but to bring the car in for a detailed quote. Clearly, a ploy to sell me stuff once I'm there. I've done business with this particular Firestone before because I have a guy there who services my car for inspection, so I have some sort of loyalty to them.

09-12-2009, 05:03 PM
There is no A/C, P/S interference charge! Nothing needs to be done to the A/C to do this job. The P/S pump needs to be removed to do the job but that is already built into the labor to do the job in the first place!

09-12-2009, 05:41 PM
It is a weird charge but am I to do? That's the problem with mechanics and auto shops. I'm still going to check a few other places, but there are very few to begin with. Meineke... maybe Midas, though I'm almost certain they'll want close to $1500. Smaller independent shops might not be expensive but, in my experience, are less trust worthy. So, once again, when it comes to auto work, I might have to kiss the ring.

09-22-2009, 10:36 AM
I had the lower intake manifold gasket replaced by Firestone. It cost me $880. So far, so good. I gotta now learn to trust the car and its high running temperatures. The Malibu does seem to run hotter than most cars I've owned.

09-22-2009, 11:20 AM
$880 sounds about right for a shop, maybe even fair for some higher cost regions like NYC.

Another symptom I was with mine was a gradual increase in oil dipstick level - leaking coolant going into oil sump.

10-08-2009, 10:54 AM
I had the same problem with coolant smell, falling coolant level and no evidence of a leak. Turned out to be the intake gasket. Leak was located in an area where it would drip down onto or close to the exhaust manifold and evaporate. Don't hesitate and get this done. I'm getting ready to tear into my 3.1L because I just turn the oil into milk last night. fun stuff.

10-08-2009, 02:23 PM
A fun job (well, once it is done). If you have a digital camera, take a lot of photos as you work you way along. It helps sort out the routing and exact placement of things as you put it back together.

10-09-2009, 07:12 PM
Buy the Dorman kit for the intake gaskets,made out of metal instead of plastic and come with new intake bolts.Also make sure you have the push rods in the right spots or the valves will bend if you do not.The pushrods are 2 differant lengths,long and short.

10-13-2009, 11:52 AM
I'm taking plenty of pics as I'm not as comfortable as I'd like to be on the newer vehicles. Everything is laid out in order and labeled as well.

I decided to put in the extra time to pull the heads as well. It looks like the rear intake gasket around the lower water channel on the driver side failed (cork surrounded by rubber????). The block, heads and intake seem to be fine. I did notice that a couple of the water channels were blocked so I cleared them. Funny thing is that these were on the opposite side from the gasket failure.

I was going to upload a couple of pictures for the curious, but I keep getting upload failures (even after resizing pics to be below 100k). Well, if you're curious or need reference pics, please feel free to contact me directly.

10-13-2009, 06:52 PM
Here's your photos


10-13-2009, 06:55 PM
I hate to say this but if you ran it at all with the oil that milky I would suggest getting a used engine. The lower ends on these are very sensitive to coolant being in the oil. You will likely end up with a lower end knock within a couple of months if the bearings have been compromised. If you make it past a couple of months than the chances get better for not having a terminal issue.

10-15-2009, 12:36 PM
I've gotten the heads pulled off and the upper engine cleared of oil. The pan has been emptied and the engine has been draining for the last few days. The plan at this point is to finish pulling parts (oil pan & oil pump drive) and clean out as much of the oil as I can.

My neighbor, who works as a mechanic for a Chevy dealership, took a look at the block last night. He seems to think that the engine looks to be in pretty good shape and we couldn't find any metal shavings in the oil.

I'm concerned about the lower end as well, but I'm going to see if I can get lucky and squeeze a few more miles out of this engine before giving up on it. I'll know more this weekend and will keep you posted.

10-15-2009, 12:45 PM
Like I said you'll know within a couple months. You literally have about 6 more bolts and the engine is out. That is seriously a lot of milky oil. If I pulled the oil cap and saw that on a customers car I wouldn't give them any option besides replacing the motor.

10-15-2009, 03:29 PM
It's hard to make out in the pics but why is it that it looks like you still have your back rockers, pushrods, possibly valve cover and alternator and coil pack still attached? That is a lot of coolant in the engine, and you might want to have checked that the head gaskets were sealing. If the engine wasn't knocking any before you took it apart and you get all the coolant cleaned out, the engine probably will survive.

10-17-2009, 09:10 PM
Pics were taken during the tear down. These were just the best at illustrating what I saw when I started taking her apart. Only things left to pull and clean at this point is the oil pan and pump. Of course the pan is refusing to budge. LOL wouldn't be a chevy otherwise!!!

10-19-2009, 10:53 AM
Any suggestions on the easiest way to get the oil pan to clear the crank. I'm thinking of unbolting the motor mounts and lifting with an engine hoist. thoughts?

10-24-2009, 10:06 PM
Did end up using an engine hoist and unbolting the passenger and front driver motor mounts. Did not find any shavings or fragments in the oil pan. Everything's been cleaned and reassembly has begun. I will keep everyone posted.

10-25-2009, 04:38 PM
WOW!!! Awesome pics! You're quite the dare devil! Suddenly what I paid to get my car fixed doesn't seem to be much.

11-02-2009, 10:12 AM
SUCCESS! Got the car started again yesterday. Runs well and I do need to chase down a fuel leak. I'm cautiously optimistic. Thanks for all the great feedback and assistance with this!

11-02-2009, 11:09 AM
Runs well and I do need to chase down a fuel leak. I'm cautiously optimistic.

The next time you do the intake gaskets you don't need to disconnect the fuel lines. Leave them connected to the fuel rail. Remove the bolt that secures the lines to the bracket on the rear head. Then just swing the injectors/rail/lines out of the way.

11-02-2009, 10:17 PM
Curious. I have the upper intake off again. Ignition is on the on position. No leak is evident. I can see fuel puddled on the lower intake from yesterday but that is all. So what would cause a fuel leak while driving? I ran through almost half a tank of gas in 10 miles! thoughts?

11-02-2009, 11:00 PM
I would think it'd have to be either at the fuel oring on the pressure line or the pressure regulator, or one of injector O-rings in the fuel rail. Check at all the oring locations.

11-02-2009, 11:26 PM
You might have to key it up several times to build pressure back into the rail.

11-14-2009, 12:44 AM
Success. Finally ended up replacing upper and lower o-rings on the injectors and both fuel rail o-rings. Afterwards there was zero fuel flow to the rail. I tracked it back to the fuel pump and, after testing, dis-assembled the fuel pump to replace the pick-up filter since the screen was clear ($8 filter vs $265 fuel pump). That solved the pressure problem and the car started immediately. Did one final oil change after 100 miles and added a quart of oil conditioner for good measure. Everything seems to be fine now. No leaks, no smoke, no unusual noises. Now to wait and see....

Thanks for the help everyone.

11-14-2009, 12:51 PM
dis-assembled the fuel pump to replace the pick-up filter since the screen was clear ($8 filter vs $265 fuel pump). That solved the pressure problem and the car started immediately.

I would put money on the pump actually being the problem. After you banged it around removing the tank, lock ring, pulling the pump out, changing the sock, reinstalling everything. the fuel pump started working again. Next time you have no pressure, probably be soon, just wack the bottom of the tank with a rubber mallet under the fuel pump while somebody cranks it over. Either the car will start or you will hear the pump trying to work.

11-14-2009, 01:19 PM
Also check if the fuel filter is plugged up and yes a plugged up fuel filter will kill a fuel pump by putting a strain on the fuel pump which is not good.Make sure you get a Delphi pump if it goes bad and avoid aftermarket pumps made by Bosch,Airtex and Carter which have high failure rates.

11-14-2009, 06:22 PM
I have never had a plugged fuel filter cause a vehicle not to start. If it is that plugged the damage is already done to the pump. I still have customers that think a new filter will solve the problem also, and it never does!

11-14-2009, 07:59 PM
I don't think I ever seen a fuel filter plugged so bad the engine wouldn't start either. I think I seen some plugged so bad they affected engine performance some though, but usually it's just a contributing factor. I think a fuel pump that's going out might plug up a filter and a plugged filter might cause a pump to go out vice versa.

11-14-2009, 08:12 PM
I have seen a few fuel pumps go bad due to a badly plugged up fuel filter and one was an Oldsmobile.It will sometimes,sometimes have no power and find out the fuel filter is plugged up after blowing through it.I know Airtex is one that will not warranty a fuel pump if the fuel filter is not changed at the same timeMy father had a blazer come back a couple weeks once after the fuel filter was changed,fuel pump went out.

11-16-2009, 09:42 AM
recently I had a simular problem and it wasnt nothing but a small hole in my upper right radiator rubber hole's, which allowed antifreeze to squirt onto the engine,which was causing me to smell anitfreeze..................

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