Electrical gremlins in my engine wiring?

[static667]

I always seem to find the screwy issues that stump everybody so I may as well throw out another one.

When my MAF is plugged in, my car runs sporadically. It may run right for a while then turn to crap or it will just run like crap all together. I'll have a low, rough idle, occasional idle surging, bad/slow throttle response, and stuttering acceleration. When I disconnect the MAF, it runs like it should just without cruise control and no throttle reaponse when the brake is depressed. I thought that the MAF was the culprit so, I replaced it. It ran okay for a few days then the issues returned. Now I have new issue that happens irregularly. Sometimes at startup, and once while driving at low speed, my EML, yellow brake, and traction control lights come on, (my SES is always on) and my car nearly refuses to run. The idle goes up to around 1,000 RPMs, it runs very roughly, and when you apply throttle, it surges rapidly between 500 and 1,800 RPMs.

I'll shut the car off and mess with the MAF connection. If its plugged in, I unplug it and vice versa. Sometimes a simple unplug or plug will fix it but, sometimes it won't. I'll mess with the connection until my car decides to run.
I'm guessing that I have an electrical issue in my wiring harness somewhere. I really don't know. Help!

Sent from my yet to be hacked GS3.

[danewilson77]

Kyle, was it a high quality MAF sensor?

[Ryans323i]

This is a wild guess, but it sounds like a DME problem. Sometimes the car recognizes the new parts and other times it doesn't. I checked you DME thread, and there wasn't an update. Did you ever get that handled?

[static667]

The second MAF was a better one than the first. If its a DME issue, I guess I can get one from a wrecked 330 and just align the EWS. I'm hoping not to have to put down the coin for it.

Sent from my yet to be hacked GS3.

[LivesNearCostco]

If you just had the traction control and yellow brake light came on, I would diagnose it as dirty/failed wheel speed sensor, failed/miscalibrated steering angle sensor, or failed DSC module. And I would recommend cleaning each wheel speed sensor (each held in with one bolt, need 6mm or 7mm hex socket to remove). That could also explain cruise control issues and any weird speedo readings, but don't see how that would be tied to the MAF in any way.

Have you read the codes?

[static667]

If you just had the traction control and yellow brake light came on, I would diagnose it as dirty/failed wheel speed sensor, failed/miscalibrated steering angle sensor, or failed DSC module. And I would recommend cleaning each wheel speed sensor (each held in with one bolt, need 6mm or 7mm hex socket to remove). That could also explain cruise control issues and any weird speedo readings, but don't see how that would be tied to the MAF in any way.

Have you read the codes?

The cruise control doesn't operate when the MAF is disconnected. The DSC and brake light always come on with the EML light, too. I could probably use to clean the speed sensors anyway but, I don't believe that to be my issue. I'll give it a try when I have a second to yank my wheels off.

Sent from my yet to be hacked GS3.