1993 Bonneville starts then immediately stalls, help!

[bobkat]

When I start the car it will crank right up first try everytime, the rpms will soar to a higher than normal idle level and then as quickly as this all happens the rpms tumble and the car stalls/cuts off. Depressing the gas pedal does nothing, the car will always stall every time.

What I have done so far is replaced the fuel filter and throttle position sensor, also I have tried cleaning the MAF. The problem still exists.

Any suggestions? I wanted to post on here before I have the car towed to a repair shop.

I pulled the codes by the way and its 22 TPS (signal voltage low). Again I replaced this sensor.

After reading some other posts I am wondering if it could be a bad PCM, after all its probably still the original and the car is 17 years old now. I am not even sure where the PCM is located in my car and if I could replace it myself to save money.

Any input would be greatly appreciated.

Thanks!
-Bobby

[bobkat]

Looking on auto-zone.com I notice there is an "engine control computer" and an "ignition control module". Not sure which of these if any could be the source of the problem. Probably would behoove me to purchase a manual for the vehicle. There is also an "idle air control valve" which seems suspect as well. I don't want to just guess and unnecessarily replace parts though, but I am trying to avoid taking it to the shop.

[1oldman]

When I start the car it will crank right up first try everytime, the rpms will soar to a higher than normal idle level and then as quickly as this all happens the rpms tumble and the car stalls/cuts off. Depressing the gas pedal does nothing, the car will always stall every time.

What I have done so far is replaced the fuel filter and throttle position sensor, also I have tried cleaning the MAF. The problem still exists.

Any suggestions? I wanted to post on here before I have the car towed to a repair shop.

I pulled the codes by the way and its 22 TPS (signal voltage low). Again I replaced this sensor.

After reading some other posts I am wondering if it could be a bad PCM, after all its probably still the original and the car is 17 years old now. I am not even sure where the PCM is located in my car and if I could replace it myself to save money.

Any input would be greatly appreciated.

Thanks!
-Bobby

Check that TPS plug too. If it doesn't make good contact, you will get the same problem as if the TPS is bad. I am not familiar with the type plug that is on the '93. If the plug contacts are round, that could very well be the problem. If the connector makes sort of a "T", then I doubt that that is the problem.

Go to your public library first. I use to use them all the time when I was close. I'm not close any more, so I have the FSM's and a Haynes, the Haynes is not as good as the Chilton's were 20 or so years ago.

Yes, good idea to get a book, even better, get the FSM's from Helm. -BC

[Jrs3800]

Sounds a lot like the ICM is rattling the injectors, and if it runs for a couple of seconds you have spark... The Ignition Module is what actually starts the car, after 400 Rpms the PCM should take over, there is a handshake between the ICM and PCM to let the PCM have the controls...

And you already corrected the TPS.... By any chance has the code 22 came back?