coreyb

Hey guys, I just picked up a pretty nice HHR Panel wagon to use for my business. I got a good deal on it, so I assumed I'd have to do some work/have some work done. It's pulling 3300RPM at 60MPH on the highway, so I'm assuming it's not shifting into 4th gear. It's also shifting hard into 2nd and less hard into 3rd. When you first drive it and it's cool, it shifts smooth into 2nd and 3rd.

No codes stored, no check engine light.

I've read about the solenoid causing issues, but being that 4th seems to be missing, do you guys thing it's even worth jacking with the solenoid? Or just drop it at the trans shop and bite the bullet?

Thank you!

firemangeorge

Welcome
Question. Is the Check Engine Light on ? If so, pull the codes and see if it points to a trans problem. Post any code numbers here. Numbers only.
Also. Certain trouble codes will cause hard shifting. GM’s way of telling Joe consumer to get the car checked.

RJ_RS_SS_350

Hi Corey, to the forums!

Is the CheckEngineLight (CEL) illuminated? If so, post the alphanumeric codes here, don't bother with the descriptions, they are often misunderstood. You should be able to get the codes read at your chain auto parts store for free.

coreyb

Sorry, no codes and no CEL. I meant to say that in the post.

coreyb

No code, no light. Post updated with that info. My bad!

RJ_RS_SS_350

So you've checked for codes? Pending codes won't light the CEL, but could help diagnose.

coreyb

Yes sir. Theres a P0171 stored which is likely a vacuum leak. I should also say that it feels similar to a torque converter lockup issue I had on a Beretta Z26 back in the day -- if my memory serves me correctly. On the highway, the HHR is pulling 3000RPM at 60 and if I let off the gas, the RPMs drop down to 2000... When I get back on the gas, it kind of "freewheels" up to 3000 and catches with a very light bump.

I'm going to get it up on my lift and check the fluid tomorrow. I've already been under it once and at 150k miles it's crazy that there aren't any leaks. No oil, no trans fluid, nothing.

RJ_RS_SS_350

https://www.obd-codes.com/p0171

Fixes start with cleaning the MAF sensor with specific MAF cleaner..

Is this code pending, current, or historic?

coreyb

It's a confirmed code.

RJ_RS_SS_350

If that is the same as current, then it is the cause of your shifting issues.