'92 Olds Cutlass S 3.1 Stumbling on Acceleration

[mgrinnell]

Good Morning,

 

I have recently posted about my '92 Olds and how I replaced the fuel pressure regulator to get it to start again. In diagnosing and fixing the starting problem I replaced the ECM and then fuel injectors and finally a new fuel pressure regulator fixed the starting problem. Since then, however, if I very gently give it gas it will accelerate. If I have to accelerate more quickly, however, I press the peddle down and the engine sputters but eventually takes off. It stumbles as it accelerates. I replaced the throttle position sensor yesterday thinking that was the problem. I am getting a check engine light but in trying to pull the codes all I get is 12 which is obviously indicating that the system thinks there is no problem. Other than TPS not sure where to look next. I thought for sure it was the TPS unless my new one is defective.

 

Best Regards,

 

Mike

[mgrinnell]

Good Morning,

 

I have recently posted about my '92 Olds and how I replaced the fuel pressure regulator to get it to start again. In diagnosing and fixing the starting problem I replaced the ECM and then fuel injectors and finally a new fuel pressure regulator fixed the starting problem. Since then, however, if I very gently give it gas it will accelerate. If I have to accelerate more quickly, however, I press the peddle down and the engine sputters but eventually takes off. It stumbles as it accelerates. I replaced the throttle position sensor yesterday thinking that was the problem. I am getting a check engine light but in trying to pull the codes all I get is 12 which is obviously indicating that the system thinks there is no problem. Other than TPS not sure where to look next. I thought for sure it was the TPS unless my new one is defective.

 

Best Regards,

 

Mike

 

Solved this -- first thought it might be the EGR valve but after thinking about it for a while I figured I'd better check MAP sensor even though I replaced it a couple years ago. Turns out all my jostling about the engine pulled the vacuum line out of the MAP sensor -- reconnected and voila! Good as new.

[Imp558]

You might want to disconnect the battery for a while and let the PCM forget the code. Did it set a code/ turn on the check engine lamp?

[mgrinnell]

You might want to disconnect the battery for a while and let the PCM forget the code. Did it set a code/ turn on the check engine lamp?

 

Actually, I had pulled the fuse to clear the codes. Even with the vacuum hose to the MAP sensor disconnected the SES lit but no code was registered -- a fact I find odd.