i just replaced the harmonic balancer and the crank sensor, which helped, but still doesn''''''''t run correctly. I have a 95 Lesabre with the 3800 engine, and it has troubles idling and often will out of no where stop running. now I found another problem that my car needs a new ECU because the computer cant link with the system to read my check engine light. Just bought the car about a week ago for $600 because at the time, it ran with no problem, only harmonic balancer was making some noise. <! Message ''''''''"" >






got a scanner from a local auto parts store that worked for the buick and it gave me EGR insufficient flow and EGR pintle position circuit codes. removed EGR and found quite a bit if carbon built up in it, but could not get pintle to seal. going to head to a junkyard monday to see if i cant find one for cheap and hopefully will fix the problem. other than those 2 codes, nothing else is showing up on scanner.

can the EGR really prevent the engine from running correctly? seems slightly odd for it to do so with it being there for just recirculating un-used gas from the exhaust
Edited by: samueljackson

 

yes a clogged egr can make an engine run very weird if at all. but before replacing, you can usually clean them with carb cleaner and they will be good to go for a while. If you go with a used one, check the oe #s on them. if your # has a "N" (either at the beginning or the end, i dont remember), make sure the replacement does too. that signifies a negative pressure feedback. they are not interchangable.





p.s. be sure to use a new gasket.

 

Update to the issue:

replaced thermostat, harmonic balancer, crank sensor, vacuum lines, and egr.

Tested coil packs, ICM, throttle position sensor, fuel pressure. All tested good

With all thats been replaced, it runs better than before, chugs and kills still, just not as often.

We did notice a hissing coming from the egr/manifold area and a small amount of coolant leaking from the lower intake, but not enough to hit the ground.

 

forgot to mention with the ICM testing, ran it about 6 times trying to get it as close to operating temp as possible. even brought a new one home and put it in with no change in performance. so i removed the new one and put the old one back in

 

another update. drove the lesabre up to the auto store and it died on the way back several times. crank it, it would chug and die. my buddy told me to keep starting it and he unplugged my MAF sensor, and it fired right up and drove the rest of the way home with no problem.

 

they make a cleaner designed to safely work on the maf sensors. Considering the price, I''d try that first. that will work most of the time.





but the mention of coolant on the LIM is NOT a good thing, and could very well be causing problems. If it lets coolant out, it can also let air in. which will cause you to run lean. Not good. the L36 is known for gaket and uim problems.





read the 1st and 3rd article here http://www.pontiacbonnevilleclub.com...wforum.php?f=5 3





It will cost you about $200 in parts, but it will be cheap insurance to prevent a seized engine.

 

Workin on the car today, and found a constant issue. The car will not run with the MAF plugged in. When unplugged, it will start and run seemingly just fine, but expectedly running rich. Bought a new MAF sensor and it didnt do anything. Do i need to start it without it so it will run, then plug it in for the sensor to read and get settled in? I also purchased oil, coolant, and the LIM/UIM for replacement before i found the MAF mystery.