my friend has a 1992 buick lesabre that will start and drive fine, but after 10 minutes of driving it just shuts off with no warning lights. after sitting for about 10 minutes it will usually start right up and go another 10 minutes. the intake is getting hot, the throttle air sensor is getting super hot and the ECM? directly under the coil pack is getting even hotter. we have replaced the throttle air sensor and it''''s still yet getting super hot. i have looked on other threads and now suspect the crank sensor, but would that cause the intake to get overly hot? i think that it''''s getting hot due to the air sensor (heat transfer) but would the crank sensor have anything to do with that as well as the ECM? i think that the best thing for the car is a 44 magnum, but he thinks differently. granted it''''s a good car otherwise, but what on earth can it be? any help would be greatly appreciated. Edited by: nesral

 

Iwould remove and have the ICM (ignition control module)tested. most parts stores can test them for free. thats the thing under the coils you called the ecm. the crank sensor on these cars will almost always just fail, and not be intermittant. and if it failed, it would not start at all.





p.s. ECM (engine control module) is reference to the computer. and technically he has a PCM (powertrain control module), as it controls the trans, and not just the engine.

 

ICM, sorry. he has had it checked out twice and it checked out ok.

 

does it kinda "chug" when it dies, or is it more of an instant thing?

 

occasionaly, it does a very slight chug, but most of the time it''s rather instant

 

if it mostly dies instantly, i would think it to be an electrical issue with the ignition. but if it sometimes chugs, you may want to get a fuel pressure test just to write it off as a possibility.

 

the fuel pressure has checked at 40 pounds of pressure. i suppose that''s good.

 

40psi when. prime, idle, or wot?





either way, it is slightly low. iirc the range is 42-47. not too bad, but slightly low.

 

when the fuel pump was tested, it was at idle and held steady at 40. the fuel pump and tank were out of a 89 buick century from a salvage yard. we replaced the fuel pump with a new one. it looks a little smaller. if it''''s the fuel pump, why would it take a 10 minute wait before start-up? or....if it''''s the ICM, what kins of problems would it cause for the transmission? Edited by: nesral

 

well, i think that we finally found the problem...the crank sensor is cracked and the part of it where you plug into wobbles. but, how can it be a crank sensor when it''s located on the water pump and the crank is down at the bottom of the engine? also, what on earth is the sensor on the passenger side at the back of the engine down at the bottom?