I have a 1991 Caprice with a .........?

Question

I have a 1991 Caprice with a 5.0 v8. The car has been taken care of emaculately!, However when the car reaches full opp. temp. and I try to start out from a dead stop the entire ignition system cuts in and out. I have checked the fuel pump, replaced the distributer cap, rotor, wires, ignition mod. , coil, ignition swich, all filters and the problem persists! The car starts good even in cold weather and idols smooth. the engine is in good shape it burns no oil or makes any strange sounds. Its driveing me crazy!!!! I have also checked all ignition wires to and from the distributer but found no falts. anyone have any ideas????

I also have replaced the TPS and no trouble codes are showing at all!

The car has no mass air flow sensor and the TPS has been replaced. the transmission shifts good and is smooth in its operation! The trouble is electrical in nature. the entire ignition system cuts in and out just like if you would turn the ignition key off and on while driveing

And yes! the trouble light works just fine!

I do not believe its the timing chain as the car idols smooth and runs at high speeds well. all the fuel lines are metal so fuel line collapse is unlikely

I did however notice some rust on the coil pick up inside the distributer I wonder if I should spray some electrical cleaner inside the distributer to clean all the visible rust off of it?

Answer 1

This sounds like a primary ignition problem, you have replaced everythind in your secoundary ignition system so we can rule all of those as problems. I would pop out the dist. and replace the pick-up coil and inspect the reluctor on the dist shaft. but it sounds like when hot, one of those little wires in the pick-up are separting and not sending a signal to the mod. and no spark.
alsc inspect the reluctor for cracks magnets do crack.I have only seen 1 in thirty years but it drove me crazy also good luck

Answer 2

Are you sure the check engine light is functioning? Does the light come on when you turn the key on? Sorry if you know better. If yes flush your injectors, it's sounds like you know how to take care of a car, but flushing the injectors came after rebuilding carbs.. They get a carbon buildup, looks like a dirty oven, or slug on a manifold. The other if the check engine light isn't working is a Torq converter clutch solenoid, this makes the transmission act like a Manuel. So when warm at a stop it acts like the clutch is out on acceleration.

Answer 3

i own a repair shop,in Tennessee,and i had one that done this in the shop once,what i fund it to be was a fuel line collapsing under pressure,and it would temporarily shut off the fuel supply to it,and one another vehicle that was acting like that i found t to have a bad timing chain and gears in it,and when you would try to take off it would act like i was going to shut off,and what it was doing was advancing the timing on it ,and making it cut out,but is was caused by the chain and gears being so worn out hat it could only advance the timing so far,and that wasn't far enough to make up for the wear and tear in the chain ,and gears if i wa you id check the free play in the chain,i think you might find your problem there,Chevy's are well known for wearing out timing gears and chains,,good luck i hope this help,s.

Answer 4

try the throttle positioning sensor. it may break down when hot. mass air flow sensor could also be bad