'98 Sunfire SHUTS OFF while driving

Ok, I have read most of the threads but I still need help with my problem.

I have a ’98 Sunfire 2.4L with 77k miles on it. Here is my dilemma:

ONLY in the summer (this does not happen in the winter, even if I drive for 10 hrs straight) when I’m driving my car, all of a sudden the check engine light shows up and the car dies!!!! I have to pull over (w/o power steering!!) and start my car 3 x’s until the check engine light goes off and the car runs fine for about 3 minutes. Needless to say, I have to do this about 10 x’s in an hour. Short of having to quit my job and go on public aide, I need to get this fixed and the “guys” at Pontiac are telling me it could be 1 of 300 different things. Well if I have to send 5K I might as well buy a new car, but at this point in time I can not afford it. Any help/suggestions will be GREATLY APPRECIATED!!!!!!

did you get a diagnostic done? the car starts and drives, but randomly shuts off. does it "choke" out like it loses power then stalls, or does it just shut off without any kind of warning? Have you done a fuel system flush? had the fuel pump pressure tested? only in the summer, hhmmmm. not the TPS, maybe the Idle air control, but that is useless at anything off idle, nevermind.

get the fuel system flushed/cleaned and tested for pressure. it's due anyway. then lets work on the ignition, perhaps a bad CPS (crank or cam) that fails when hot (thinking crank). the computer would lose the timing for the spark, and throw a CEL just before the motor died due to extreme timing loss.

work on the fuel system first though and eliminate the thing that are due for PM.

A lot of this was just thinking out loud (well, sorta) to help determine a possible solution, if nothing I mentioned works, then, the dealer knows best. and take the car to another dealer, just like a doctor, for a second opinion if need be (i know, more money).

Thanks for the reply! No choke, the car just shuts off, I feel a little slip, and then the check engine light comes on, I two foot it & the car bucks HARD as it changes gears. If the computer would lose the timing for the spark, and throw a CEL just before the motor died due to extreme timing loss, would this show up as a diagnostic code? I took my car to Auto Zone last night, they said, I need a new TPS & O2 sensor and that I have a misfire on 3. If I get the sensors replaced and a basic tune-up, that should do the trick. Does this sound right to you??? Again thanks for your time!!!

sometimes, when you get multiple emission codes, it means that there is an issue with the ECM. I'd get the car on a computer to see what's going on and also test the sensors the codes listed and their individual harness connections. it means you have to get a Haynes manual, and a multimeter if you don't have one.

If you test the sensors and the connections and they are good, and the dealer says they are bad according to the ECM, let them know you tested the sensors and the computer is bad. Your computer controls your shifting as well, so all this could be a result of a defective computer. around $200 (thats a guesstimate) for the computer, and you can install it yourself in about 1 hour (at a slow pace)

*EDIT* you need the new computer flashed at the dealer when it's installed IIRC

ALSO - GET THE TUNE UP!!! eliminate the cheaper alternatives first

I ask that question bc my car is doing the same thing...but it does it when ever it wants....therefor im usually going down hill or turning when it does happen. I was told that I needed a fuel filter well that didnt work. I got a tune up, oil change, changed the air filter, got a fuel system cleaning thing ran threw my engine, and now they want to tell me I need a new fuel pump which i was quoted at $400. I've only had this car 2 months and its getting fustrating. PLS let me know if you have found out anything on your car.......Thanxs Bunches

Two things that can cause your problems. One is the security system that may be malfunctioning. The second is the crank position sensor. If the security light comes on the car will stop this system is hard to understand since none of the manufacturers will allow much information to be given out on it. The second item is the crank position sensor. If it is going bad the car will shut off but will restart most times and run for a while. If the sensor is intermittant, if you replace the sensor you should solve your problem.