Just got a 2011 HHR lt 2.2 174k miles, so many problems, speakers were all four ruined from water damage, replaced now working fine.
The gages all go crazy; gas, power steering, rpm, everything on the dash, even the cold air stops when these probpems happen.
Replaced tcm and problem persisted, put ground wire on battery to the positive to drain the computers, and after a few minutes everything was fixed, worked for 30 minutes, went to bed, problems back, nothing works.

I think these 3 problems are tied together, after a week of googling and trying, could be ecm, tcu, ground, battery, faulty wire in dash, fuses. Ive tested all these and they seem to work but could still be bad. Anyone have advice this seems to be a very common problem with no solutions and seems there was a recall for the eps motor in 2014.

why did it work after draining the computers? Any advice please.

 

Welcome to the site , your battery might be the problem, have it load tested , anything under 12.4 bolts and the computers are very grumpy! Also have a look at the under hood fuse box , the halves loosen up and cause havoc

https://www.chevyhhr.net/forums/how-...rmation-59520/

The EPS motor is an extended warranty, not a recall.
The ignition switch was the recall, was it done?

 

Cleaned the halves with rubbing alcohol, battery is 12.8 volts. New tcm, grounded tcm, reset computer, cleaned terminal, pulled power steering fuse. Thank you ill try cleaning connections to computer. Any other ideas? Or anyone else.

 

My favourite, check for broken or loose and or corroded ground wires.

 

You say you replaced the TCM ? Why ? All that you described are related to the ECM or maybe the PCM.

It sounds like a low voltage or bad connection issue. I would start with checking the main + cable connection at the underhood fuse box.

 

my auto mechanical experience includes 20 hours in Car mechanic simulator 2016, and several google searches. My grandpa is helping me work on the car im only 21 lol.

 

do u have abs ? if so u may try unplugging it and c if the gauges still go crazy i only say cuz i had a 08 that did the same and we found the abs brain was crazy and messing with the rest as soon as we replaced and flashed it its been great 1.5 years later just my 2 cents , gl