1991 Oldsmobile Cutlass lunging.

WIMSATTJ

MEMBER
1991 OLDSMOBILE CUTLASS
6 CYL
FWD
AUTOMATIC
197,305 MILES

I need help guys. My car is my only form of transportation, I cannot afford to even buy another cheap used car. Carbon deposits are building up in the exaust, and my car floods when it is warmed up. It runs better when it is cold, but lunges 90% of the time. Computer code reads knock sensor/timing memory. ! The second part I cannot remember. It is one code, my tech said it was dependant on the year. He's not sure but he beleaves it is the eprom memory chip in the computer, but would that not read multiple codes? I'm gettting one code. I cannot afford to experiment. I must get the answer soon, before my catalitic converter clogs, and carbon deposits start destroying my engine. It was better before the power was disconnected when the starter was replaced. It was only dieing at stop lights every once in a while, now it is a whole lot worse. Please help me I am poor and lost.

1 Reply

SERVICE WRITER

MECHANIC
9,123 POSTS

What is the code number that is showing?

Is this a 3.1 motor?

This is what I believe at this point. There is a rich condition happening causing the excessive carbon.

Since symptoms changed when the battery was diwsconnected, it says to me the PCM memory was cleared and it had to relearn.

My gut feel is a bad computer. Anyways,

IF it is code 33 or 35, otherwise ignore this.
HAve your tech check some wiring. The green wire with the black stripe coming from the iac to the pcm for a short to ground. The short can occur because of an oil leak which caused the wrapping to come off the wiring harness underneath the a/c compressor.
The harness can rub against the bracket that holds the harness away from the belts.

If this is code 45, other wise ignore this too.

Clean the throttle body.
Make sure the EGR is not sticking.
Check the injector pulse width.