Sunfire starting problem

[bauekel]

I have a 96 pontiac sunfire, 2.2 L engine with 110,000 miles. It will start up perfectly fine from a cold state, but doesn't like to start when the engine is warm. This has been going on for about a year and is continually getting worse.

When I try to start the engine while warm, it will turn over normally but it won't fire. When the car does eventually fire, the engine will catch, shudder and chug as if it is not getting enough gas. Then the car will jerk and stall out.

If I press the gas pedal when the engine fires, I can push through the chugging, stuttering stage and the engine will stay running but the idle will be very rough.

If I let the car sit for couple hours after it was warmed up, (so the engine is cool again) it will start up normally.

I have had new plugs and wires installed.
Fuel pump tested o.k.
Fuel Filter replaced.
Crank shaft sensor replaced.
I had the entire fuel system and spark plugs thouroughly cleaned.
No sensor lights are on.

I have invested over $1000 in the car and it still has this problem. Does anyone know what is going on? I would really appreciate any input as I am really not in a situation where I can afford to buy a new car.
Thanks so much!
-Kelly

[lilangelmom]

I have virtually the same problem with my vehicle.. only its 2.4 l engine.. it was suggested to me that it could be the ignition module.. I dont know much about cars.. but perhaps its worth a try. lol let me know how it works out..

[manicmechanix]

Originally Posted by bauekel

I have a 96 pontiac sunfire, 2.2 L engine with 110,000 miles. It will start up perfectly fine from a cold state, but doesn't like to start when the engine is warm. This has been going on for about a year and is continually getting worse.

When I try to start the engine while warm, it will turn over normally but it won't fire. When the car does eventually fire, the engine will catch, shudder and chug as if it is not getting enough gas. Then the car will jerk and stall out.

If I press the gas pedal when the engine fires, I can push through the chugging, stuttering stage and the engine will stay running but the idle will be very rough.

If I let the car sit for couple hours after it was warmed up, (so the engine is cool again) it will start up normally.

I have had new plugs and wires installed.
Fuel pump tested o.k.
Fuel Filter replaced.
Crank shaft sensor replaced.
I had the entire fuel system and spark plugs thouroughly cleaned.
No sensor lights are on.

I have invested over $1000 in the car and it still has this problem. Does anyone know what is going on? I would really appreciate any input as I am really not in a situation where I can afford to buy a new car.
Thanks so much!
-Kelly

To diagnosis your problem would probably require someone that knows what they're doing hooking up a scanner and take a good look at your TPS, ECT, MAP sensor values and other values. My guess is if it runs rough at idle when warm you probably have dirty/faulty fuel injectors. But other things can cause the problem too, vacuum leaks, EGR, poor grounds, etc. It doesn't sound like your car has been diagnosed properly. Where did you take it? Maybe you should take it to a good GM dealer. A good service department would've only need to charge you about a $80 diagnostic fee and found the problem without replacing a bunch of stuff that wasn't needed.