88 Park Avenue

Got what I think is an easy question.

Please go easy on me, this is my first post.

I have an 88 Park Avenue I recently purchased, with a known problem. I get an error code 41, which would indicate a Cam Position Sensor problem. So I replaced the sensor. Still get the code, along with the stuttering acceleration and general lack of power, which is to be expected with a bad CPS. So at this point, I believe I may need to replace the CPS magnet.

Question: Is the magnet, which according to alldatadiy.com is on the cam gear, an integral part of the cam gear, or can I buy the magnet, rip off the belt, water pump and timing cover and "simply" replace the magnet?

Am I correct in the thought process that if I have to replace the gear, I might as well replace the timing belt as well?

Standing by for any help.

Just another newbie

Hold it a sec, make sure that the wire that goes from the sensor to the ECU is not busted, or the ECU itself.

I looked at the wires and they looked good, but can't see the whole run.

I'll check voltages on the harnesses and ECM before I continue.

there is another thread in the forum about another 88 park ave, read what i said there, and check those things.

I'm having the exact same problem with my 88 park avenue. Mine started about 3 days ago. Like yourself, I changed the CPS hoping for the best. I did pull the CPS out yesterday and put a mirror in front of the small mount hole where the CPS goes and put a bright light so I could see. I then turned the engine with a wrench and watched the hole, I never did see the magnet, so I guess it's come off. My local buick dealer said that was the most common problem for a code 41. Let me know how you come out on this.

did u ever replace your magnet or did u replace the entire cam gear? mine is broken off. thanks.

I ended up replacing the magnet. Mine was the snap-in type as opposed to the bolt on type. The magnet plugs in to the back side of the cam gear. It cost $12.00 at my local Buick dealer. I went ahead and replaced the timing chain as well as the cam and crank sprockets. About $50.00 at autozone. Mine needed changing since the chain was stretched pretty good. All in all it wasn't a bad job, it was just getting to it that was a pain. One thing I did that helped out was draw a digram of the timing case cover on an empty box and put my bolts the same place they came out of because some are different lengths. Also the water pump and the oil pump are on the timing case cover but that wasn't bad. I put it all back together and started it after I filled it with oil and coolant, of course and it runs like a charm. I did mine on 10-25 and as of now I don't have any leaks and the car runs stronger with the new timing chain. Mine was stretched pretty bad. The oil pan had to come off but that was not a biggie. Didn't even have to take the starter off to get oil pan off. There was nothing around the oil pan to get in the way, so it was pretty easy. One good thing is I didn't have to put a puller on the harmonic balancer to get it off, it just slides right off as well as the crank gear. Might have to persuade it with a few taps of a hammer.I almost forgot, one other thing I did was put some J-B weld around the edge of my new magnet. The new push-in type has two small plastic keepers that is supposed to make it stay in the cam gear and it seemed pretty cheap to me so I put the J-B weld on ther for a little added insurance.

You have the 3800 motor in there right? how bad was it to take the timing cover off? the front motor mount has to be removed right? i was thinking of getting a magnet from radio shack and j-b welding it to the sprocket without removing anything. how long did it take you to do the job? If i start in the morning will I be done at nite? I am a experienced mechanic with my mustangs and v8's. I don't need any pullers for the lower crank balancer? what about the crank sensor? let me know if you can. thanks alot. I appreciate it!

You have the 3800 motor in there right? how bad was it to take the timing cover off? the front motor mount has to be removed right? i was thinking of getting a magnet from radio shack and j-b welding it to the sprocket without removing anything. how long did it take you to do the job? If i start in the morning will I be done at nite? I am a experienced mechanic with my mustangs and v8's. I don't need any pullers for the lower crank balancer? what about the crank sensor? let me know if you can. thanks alot. I appreciate it!

Yes, I have the 3800 motor. Funny you mentioned the magnet from Radio shack. I had a round magnet that fit perfect in the hole in the camshaft sprocket and J-B welded it in, gave it time to dry, but it didn't work. The magnet the dealer sell's you must be a special magnet. It's small but very strong. You DO NOT have to take a motor mount off. I changed mine in a day. You will have to take the alternator off and unbolt the power steering pump and set it out of the way. As far as the timing case cover goes, after you get everything out of the way it's not that bad. Just keep note of where the bolts go so you can install them in the same holes. The two bolts that hold the crankshaft sensor on are mounting bolts for the timing case cover. Get you a Hayne's manual from Autozone if possible, it was real helpful. My manual said you had to have a special tool when reinstalling the crankshaft position sensor, which I didn't have so I marked my timing case cover with a scribe and got it pretty close. Then after I got the timing case cover back on I installed my balancer and the crank bolt and turned it with a wrench to make sure the balancer would not hit the crankshaft sensor and to make sure the splines were lined up right. This method worked good. The crankshaft bolt takes a 1 1/8 inch wrench. You DO NOT need a puller for the balancer or the crankshaft timing sprocket, they just slide off the crankshaft. They're held in place by the keyway. You may have to encourage the balancer with a hammer but I didn't have to get rough with mine. You shouldn't have any problem since you are mechanically inclined. There are 3 small bolts that go through the oil pan and bolt to the underside of the timing case cover on the balancer end. I did have to remove my passenger tire and the dust covers under the fender to get to the balancer.The timing chain has a spring loaded tensioner that has to be taken off but this was not a big deal. I took my dust cover off that was covering the flywheel and put a big pair of vise grips on the flywheel to keep the engine from turning when I was taking the crankshaft bolt off. Anyway hope this helps. If I can help you again, let me know and let me know how your project goes.

well, things didn't go so good. i bought the factory magnet for 13 bucks at the dealer thinking things wouldn't be so bad. well after starting the project, i ran into a stripped crank pully bolt, that no way no how would come off. so i then was fustrated and tried to remedy the problem with some jb weld. after getting fustraded with jb weld flowing on the the magnet i decied to bring it to the dealer for a 430 dollar labor estimate. its being worked on as we speak. after studying the uninstall, on the new body style park avenues, the front motor mount does have to come off, cause it mounts on the timing cover. Just my luck. i'll let you know what the final dealer damage is. thansk for your help thus far. tony:)

well, things didn't go so good. i bought the factory magnet for 13 bucks at the dealer thinking things wouldn't be so bad. well after starting the project, i ran into a stripped crank pully bolt, that no way no how would come off. so i then was fustrated and tried to remedy the problem with some jb weld. after getting fustraded with jb weld flowing on the the magnet i decied to bring it to the dealer for a 430 dollar labor estimate. its being worked on as we speak. after studying the uninstall, on the new body style park avenues, the front motor mount does have to come off, cause it mounts on the timing cover. Just my luck. i'll let you know what the final dealer damage is. thansk for your help thus far. tony:)

Man, I hate it that your having problems. I wasn't aware they had changed the mount positions from 88 to 91. I know when I went to buy my magnet, the parts man told me it was about a 800 to 1000 dollar job with parts and labor. Maybe they won't clip you too bad. This sounds like one of my projects, but fortunally mine turned out good for a change. Anyway good luck on the outcome.

Man, I hate it that your having problems. I wasn't aware they had changed the mount positions from 88 to 91. I know when I went to buy my magnet, the parts man told me it was about a 800 to 1000 dollar job with parts and labor. Maybe they won't clip you too bad. This sounds like one of my projects, but fortunally mine turned out good for a change. Anyway good luck on the outcome.

well i find out tommarow nite. no more than 450 bucks or i will die!

well i find out tommarow nite. no more than 450 bucks or i will die!



well everyone, here is the damage at our lovely buick dealer. $509 dollars for a CPS magnet replacement. $450 in labor alone. did I get majorly screwed? the car runs great however. they also though managed to push in my sub floor cause they lifted the car by the floor pan and stained my white paint with grease. gotta love the buick dealer. but my car is running good. seems alot more responsive from before the magnet fell off. thanks for all the help. now all i need to do is find new rear chrome panels for my 91 ultra and we'll be in great shape. thanks everyone! :)

well everyone, here is the damage at our lovely buick dealer. $509 dollars for a CPS magnet replacement. $450 in labor alone. did I get majorly screwed? the car runs great however. they also though managed to push in my sub floor cause they lifted the car by the floor pan and stained my white paint with grease. gotta love the buick dealer. but my car is running good. seems alot more responsive from before the magnet fell off. thanks for all the help. now all i need to do is find new rear chrome panels for my 91 ultra and we'll be in great shape. thanks everyone! :)

Man what a deal. Well at least its running good. But I hated to hear the cost.

they also though managed to push in my sub floor cause they lifted the car by the floor pan and stained my white paint with grease

Ok, thats outrageous! Did they offer to clean it?

Ok, thats outrageous! Did they offer to clean it?


yes they did take it back and cleaned it up as best they can. they used the excuse of cracked clear coat which is partialy true do to it age but regardless it should have been kept cleaner.

I'm replacing the same magnet on a 91 LeSabre. I'm stuck breaking the crank bolt free. I have a flywheel holder preventing the engine from turning. I've tried my 1/2" drive breaker bar with a three foot extender pipe and pushed very hard. I'm not a small guy so I know I've applied some pretty serious torque on that bolt. I'm wondering, is it a left hand thread?

Any suggestions?

Thanks.

I'm replacing the same magnet on a 91 LeSabre. I'm stuck breaking the crank bolt free. I have a flywheel holder preventing the engine from turning. I've tried my 1/2" drive breaker bar with a three foot extender pipe and pushed very hard. I'm not a small guy so I know I've applied some pretty serious torque on that bolt. I'm wondering, is it a left hand thread?

Any suggestions?

Thanks.


Hi This is my first post here so here go's.
Had the same problem geting the crank bolt out on my 1988 Park Ave. 3800 engine. It is a standard lefty loosey bolt A friend took a look at a shop manual and says it was torked on at 180 lbs and it felt like it.
So anyway I pulled out a sparkplug and shoved some nylon rope into the cylinder to stop the engine from turning (worked like a charm) but you already have this problem solved, Went to napa and got a 6 sided impact socket put it on my 1/2 in breaker bar and had probably a 4 or 5 ft pipe on it. I was pushing so hard that wen the bolt finally started turning I thaught I was twisting the head of it off.
Oh and be carfull wile I did get the bolt out the breaker bar and pipe cocked a little to far tward the pully when I was pushing and I bent it. That was a $126 lesson lol :smile:
Any way I hope this helps good luck.