Reduced Engine Power / CEL / Stabilitrak code P2138

[ZLeeper]

I have seen many posts and been on a couple of sites but still looking for answers.
2013 ZL1 9k miles, CEL light comes on, Engine power reduced and Stabilitrak message. P2138 code always repeats. Just when I think the problem is solved and the car drives normal for a few miles, the same code reappears and car goes into limp mode. The tune has been in the car for nearly a year, no problems.

I have replaced the Accelerator Pedal switch, replaced throttle position sensor and cleaned the VMax throttle body, wiring was verified by GM mechanic to not have any shorts in those harnesses. I have confirmed with JMS about the pump voltage booster and the connecting pin harness is good. I do not have a Vitesse throttle controller.

Could the throttle body actuator malfunction to cause this code? or anything else to do with the VMAX throttle body. That is only part that might be old as it was an exchange and I do not have my stock throttle body to test that theory. I have not replaced the pigtail at the throttle position sensor.

Hoping some good answers come from this because not driving the car for 2 months is getting old.

[ZMEnow]

Potential Causes of P2138 DTC

the wiring connector or "pig tail" on the throttle body gives problems in the form of a poor connection.
The female terminals on the pigtail corrode or pull out of the connector.
Possible bare wire on pigtail shorting to ground.
The top cover on the throttle body distorted preventing the gears from turning properly. The electronic throttle body is faulty.
The accelerator pedal sensor or its wiring failed.
The engine management computer has failed.
The TPS sensors were not correlating for a few seconds and the computer needs to be cycled through its relearn phase to restore active response to the throttle body, or the computer needs reprogramming at the dealer.

The Last one isnt an option unless you have the ability to re-flash your tune yourself like an X4. If I have some time over the weekend I will read the fault codes in the service manual.. If I remember this code takes you a lot of places.. For the heck of it re-seat all the connections to the ECU.

[ZLeeper]

new update...
unplugged the JMS Power Max booster pigtail jumper and plugged back in the original accelerator pedal harness pigtail. No pump booster at all and able to drive around the car for 2 days and no codes (100 miles), no hard throttle but not necessary.
No kinks or pinches in the 5V cable to the booster and tested to see if it was grounding out. All good there. Could never go more than a few miles and the CEL and code P2138 would repeat.

The pigtail seems to check out by itself but the guys at JMS are going to send me a new pigtail anyways. Going to drive the car around some more with it unplugged. Think the mystery might have been solved. Will know more in a day or 2.

Thanks

[ZMEnow]

Originally Posted by ZLeeper

new update...
unplugged the JMS Power Max booster pigtail jumper and plugged back in the original accelerator pedal harness pigtail. No pump booster at all and able to drive around the car for 2 days and no codes (100 miles), no hard throttle but not necessary.
No kinks or pinches in the 5V cable to the booster and tested to see if it was grounding out. All good there. Could never go more than a few miles and the CEL and code P2138 would repeat.

The pigtail seems to check out by itself but the guys at JMS are going to send me a new pigtail anyways. Going to drive the car around some more with it unplugged. Think the mystery might have been solved. Will know more in a day or 2.

Thanks

Was the BAP a recent install? The guys at JMS are a good group, I had issues with ramp voltage on my install and they worked very close with me to get it resolved.

[ZLeeper]

Over 9 months on the BAP

[ZMEnow]

Originally Posted by ZLeeper

Over 9 months on the BAP

That's odd as you are just piggybacking on that harness and pulling a 5v signal to the BAP..