First off, been lurking these forums ever since I got my beautiful HHR a year or so ago. It came with an 02 sensor code but that was easy enough to fix. Preemptively, thanks for the help I'm sure I will soon receive!

I took my daughter to her ballet class today. Sat in the parking lot and idled for the whole hour she was in there because it was hot outside today. Could that be what caused this issue? 🤔 🤣

Anyways, when we went to leave, the dreaded reduced engine power indicator came on the dash. I quickly pulled into a parking lot to get off the road. I popped the hood, unplugged the ECM fuse for a good 15 minutes, popped it back in and was able to drive home with full power. CEL still on coming home.

Got home, plugged in my scanner and it showed P2122 code. Searched this wonderful forum and there's all kinds of different things it could be apparently. Question is, would it most likely actually be the pedal position sensor since I was able to make it home after unplugging that fuse? Or, since it's an '06, would it most likely be some bad connection somewhere? I saw on one post where a guy suggested it was a passthrough connection for the fuel pump that gets grimy but I can't for the life of me find that dang connector 🤣 (not a car guy by any means. Also, don't have a jack at the moment to be able to fit under there to see easily)

Y'all give me some updated 2025 information regarding this. Thanks a billion tons! 💪

 

You will need to do some testing to answer your questions,

 

Nothing to do with the fuel pump.

There are 2 inputs on the APP sensor, one is 5V ref the other is low ref. One or both of them is not connecting. The other ends go to the ECM.
Low ref is digital ground, it could measure between 0v and 3.5V, but usually 0V.

 

https://www.obd-codes.com/p2122

TPS could be loose, could be bad connection

 

P2122 means “Accelerator Pedal Position (APP) Sensor 1 Circuit Low Voltage.” Wasn’t there a recent threat from someone who rebuilt, basically opened up, cleaned, closed up, and reinstalled his throttle position sensor with good results? A loose wire could also cause low voltage.

Apologies if I committed the sin of repeating something already stated. I was too lazy to reread the whole thread, and the context was needed for the comment to make sense, anyway.