P2138 pops up on my Buick with reduced engine power and traction control warnings. It seems to happen only when it’s raining or has recently rained, and more frequently (maybe two or three times a month) in the spring when puddles are everywhere. After reading another thread where someone’s leaky sunroof was causing this issue it seems pretty plausible that water is the real culprit and driving through the rain right before losing engine power is not just a coincidence.
Whenever I get this code I pull over, clear it, and restart the car to clear the traction control warning. After that it seems like I’m good until the next big rain storm. BUT, how do I fix it “permanently”? Throttle body and pedal have both been replaced.