Limp mode, code P2138

MWILSING

MEMBER
2014 GMC TERRAIN
3.6L
6 CYL
2WD
131,000 MILES

The car drives fine then it goes into safe mode, loses power and reduced engine power, disabling traction control, service stabilitrak warning comes on along with check engine light. The very odd thing about this is it happened a week ago, I checked for codes and reset. Now it happened again. But, both times it happened were right after I drove over rumble strips before a stop sign. I ended up turning around at exactly the same spot. Coincidence? Trouble code is P2138.

1 Reply

JACOBANDNICKOLAS

MECHANIC
108,348 POSTS

Hi,

The codes indicates the acceleration pedal position sensors (APP) are out of range of each other. Since it happened over a rumble strip, the first thing I would do is simple check to make sure the connection at the switch is tight, not corroded, and not lose or damaged. If something there is loose, the vibrations may have caused an issue.

I attached a pic below, circled the switch and highlighted where the plug will be located. If you find it to be in good condition, then it requires a testing procedure. Check this and let me know what you find.

Take care,
Joe

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