I have A 91 RS and the tach reads very high. When I start to drive the car i can go up to third gear without touching the accelerator. I have heard a few things from friends to try but always find the best info here. Any ideas? I am getting a error code. The thing about that is say if I start the car and get on the highway quickly and am moving fast it doesn't come on, but the second i slow down to exit the off ramp on comes the service engine soon light? When I get my car up here at school in a few days i am gonna attempt to display the code although I am not positive where the dlc connector is?? below the steering wheel I believe? Any help or ideas appreciated.

 

The connecter is right in front of your right knee when driving. check the codes and lets us know what comes up. Then it will be eaiser to help you.

 

Thanks, I figured That after I got the code It would be easier for people to help But i just decided to post anyway.

Thanks again

 

left knee isnt it? at least in my car

 

Next to the fuse box on my 91.

 

right knee ! .... is it different in a T/a ?


mine is on the right

 

On my SC the aldl is on the right.

 

weird i thought they were all on the left like my 90 firebird.

 

First, you'll need to acquire a GM OBD I ECM Diagnostic Trouble Code Retrieval Tool (commonly known as a paper clip to TGO members). You'll also need to have a Diagnostic Trouble Code recorder. I use a 3¼ x 5 ruled index card and genuine cedar #2 pencil, but I suppose any note pad and writing instrument will work for a first-timer.

With the engine and ignition turned off, locate the ALDL connector under the dash, just to the right of the steering wheel in the driver's foot well area. There should be a small rectangular cover over the access hole in the lower dash trim.



Insert a tool as described above (paper clip) into the 'A' and 'B' terminals on the ALDL connector:



WITHOUT STARTING the engine, turn the ignition to the "RUN" position. Watch the Malfunction Indicator Lamp (MIL) and it will begin to flash. This is also commonly called the "Service Engine Soon" or "SES" lamp. The first code will flash three times, and will usually be a code '12'. This is encoded by one flash of the lamp, a brief pause, then two successive flashes of the lamp. Each code will repeat three times, so you should see a "Code 12" flash three times. Any other error codes will follow in numerical order, and each code should flash three times. After all codes have been displayed three times, the "Code 12" will again flash three times, then all other codes will follow as described earlier. This cycle will continue until the jumper is removed or the ignition is turned off.

After you have made a note of all error codes, turn off the ignition and remove the jumper immediately. If you forget to remove the jumper and attempt to start the engine with it in place, you could damage the ECM. For this reason you should remove it immediately.

Once you have a note of all error codes, check this file for the decoding:

GM Error Codes.pdf.

You'll need Adobe Acrobat Reader to open/print the file. (See link below.)

 

Thanks a lot Vader will do. I appreciate the effort and the humor you put into helping me.

Thanks

 

the tech article says to put the paer clip in pins A and M according to your diagram, or 6 and 12 as the tech article says. is it different for different cars? i want to see if i have any codes but dont want to damage it by shorting the wrong pins. i have a 90 firebird

 

IIRC after a certain year GM changed the pinout, which means that up to a certain year, one is correct, while from that year on the other is. not sure which is for what years, though

 

If it's OBDI with a 12 pin ALDL connector, it's always A and B. This trick is not possible on any car with either partial or full OBDII system and a 16 pin ALDL connector....basically anything 1996-Present and some 1994/1995 vehicles with partial OBDII.

 

how high is your idle? sounds to me that your idle is to high if it moves buy itself. and you say the tach reads real high.

 

look into checking for vacuum leaks or a bad/stuck IAC if the codes don't turn anything up.