tomiscool

hello to everyone and thanks for your insight,
I too have a 2011 hhr with an intermitten code 2135. so far the problem has no certain pattern,although the extreme cold weather has seemed to increase this problem.I can be traveling with the cruise on, and in traffic and also just sitting idling and in park and will trigger this code and the engine will start to misfire,will not accelerate and the traction control will disingauge. i have a cheap code reader and eraser that i keep handy and plug in to the obd connector just above the drivers lft knee and can erase the code while driving.this problem seems to be a harness or connection problem and will be cking the ecm connetion.

firemangeorge

Welcome to the site.

Correct codes have a letter designation before the number. I will assume you mean P2135. Do a search here for that number. It's been discussed before. And no, I doubt the problem is an ECM connection.

Hint: P2135 points to a throttle position sensor issue.

donbrew

You need to spend a couple of hours with Google "obdii" or "obd2". You clearly don't understand what it is or how it works, it is way more complicated than this site can handle.

Oldblue

Welcome to the site, I concur with Firemangeorge and Donbrew, please spend some time to research the code it maybe a loose connection at the throttle body or a ground wire is intermittent, simply enter P2135 into the search window and read all the threads for information to point you in the correct direction.
Let us know how it goes