I have done a lot of searching through this wonderful network but it can still be a bit overwhelming. Got a used 2006 HHR 2.4 auto. I have 2 issues. After first getting it I noticed there was an issue with coming to a stop. The rpm’s would get low around 500 and it feels like it wants to stall before it catches up. And it would intermittently hard shift. Did a lot of searching on here like I said. There are no codes currently. But I’ve replaced the evaporator purge valve, Sprayed down the MAF sensor, cleaned the throttle body replaced the O2 sensors, had the ECM updated. For a full day it did great. Now it’s starting to do it again as far as the rpm issue goes. Does it wether the A/C is on or off. Havnt had the hard shifting issue yet since doing that but it’s only been a few days. Any ideas?

 

Welcome to the site, I wonder why replace those parts if there were no codes? How many miles on the HHR?
It could be timing chain, VVT camshaft phasers, alternator, serpentine belt and tensioner. But not all those .

 

Those were the things that were suggested to people who were having similar issues. 160000 miles roughly. The throttle body was pretty dirty.

 

I get that, now most of the things I listed should cause a CEL code. I suggest you just test somethings.
A : fuel pressure
B : timing chain , just remove the valve cover and inspect for slack.
C : serpentine belt and tensioner, at that mileage it might still be original and done.

 

I will give those a try on my next day off. Thanks for the advice.

 

So, if I said it is a bad lubkerwidget you would replace it?
My guess is the torque converter clutch has a problem.

 

Possibly? I’m new to working on vehicles. I have no vehicle maintenance Savvy friends or family here in SC so relying on this forum and YouTube university.

 

I would find a transmission shop that will do a free diagnostic.

 

I did that because it was my fear originally but they said the problem would be consistent for the hard shifting issue. And time is my biggest enemy. Don’t have the time or another vehicle in order drop it off with them for a few days.

 

The hard shifting is usually caused by a CheckEngineLight and not related to the transmission at all. Usually it is a VVT valve going bad, or somebody forgot to plug the MAF back in or did it poorly.
The stall when coming to a stop is most likely in the torque converter.
2 unrelated problems.
DON'T CLEAR CODES if they pop up.