11-09-2000, 11:01 PM
I'd appreciate some help with a check engine light problem. The code associated with the periodic appearance of my check engine light on my '91 9000S is 12112. The diagnostic chart I've referenced states "air-fuel mixture, engine idling (additive)". Unfortunately, this diagnosis isn't particularly clear to me. Can anyone help interpret what this really means?
11-10-2000, 02:11 AM
Have you got a lambda sensor fitted? If so could be this or the air mass meter or connections to either. If the fuel ECU misses these signals it will revert to its limp home defuelled fuel map (I think)
11-10-2000, 08:05 PM
The lambda sensor was replaced about six months ago. I'll check your suggestions and see if that helps. What's odd, though, is that the light only comes on periodically. I can go a few weeks without it on and then it will come on once or twice in a few days (lasting only for the duration of the drive--after the car sits for a short while at the stop the light usually does not come back on for the return trip).
I had the same problem on my saab 9000cde 2.3i where the check engine light would flash
while driving sometimes. When I read the fault codes off this was the same one. Are some inspection, I found the problem.It was water ingress in the Lambda (oxygen) sensor conection which is located on the drivers side under the plastic cover at the top of the engine bay. This is the main connection from the sensor to the wiring loom. Using a 8mm socket remove the cover and disconnect the sensor at this point(This connection is right beside the vacuum pump for the cruise control). check these contacts for dirt or verdegree clean as necessary & try it out.