Horace - 1/23/2019


Hello everyone! Dave here in Ithaca NY, worried about going down a "rabbit hole" regarding repairs to my 2009 HHR LS.

Last Summer my Check Engine Light came on when I was vacationing in western PA. I was on a highway and the Cruise Control wouldn't work. Then I saw the CEL.

I bought a new gas cap, thinking it would be a simple fix. But the car parts guy plugged his gizmo into the OBD port and we got the following codes:

P0700
P0974
P0455

I have been driving the car with no performance issues whatsoever since July. None.

Meanwhile I searched the forums for help, and what I learned so far is that these codes have to do with an evap leak and a sensor inside the transmission.

But nothing found indicated an easy solution. It may likely involve a bit of trial and error to repair.

In other words, a possibly quite costly trip into a RABBIT HOLE!

And now the car must pass inspection by the end of February.

It could be relatively simple, or maybe moderately difficult; or it could be even worse. I'm afraid of bringing it in for service like three or four times over several months before it's fixed, and in the end at a great cost. Or that it can't be fixed without a major investment. Some of the threads I've read about HHR electronics and sensor issues seem to end unresolved, and kinda hopeless, even after great effort and expense involving trial and error..

Nobody has a crystal ball. But I could easily fall into a rabbit hole on this one, I think.

Does anyone know a mechanic in the northeast maybe who is really familiar with this sort of GM / HHR thing? My trustworthy local mechanic says he's not the right guy for this sort of thing.

Like I said, the car is driving fine. This is frustrating for me, and I have procrastinated 8 months. If I didn't have to pass inspection I would probably continue to put it off, because nothing seems to be wrong at all!

I really miss the remote start and cruise control features, but that's all that's missing. Car runs great.

Car currently has 80,100 miles on it.

Thanks for your advice and recommendations in advance!

David
Ithaca, NY

 

OK Chinese fire drill time.
The last code P0455 deals with emissions. The other ones are first a genetic code for the transmission ( P0700) the other is for a shift solenoid in the trans (P0974).
From what has been done most frequently, is to replace the two shift solenoids in the transmission to correct the P0700 & P0974 codes.
Read this for P0455:
https://www.700r4transmissionhq.com/p0455-chevy-malibu/
As a shot in the dark your Evap canister line might be rotted by the LR tire wheel area. Other people have had this issue. Replace the rotted out section, if that's it. No need to replace the complete line.
Don't know the law for inspection as far as the check engine light is on for emission and transmission "problem"

 

Thanks. Maybe the Auto Zone gas cap wasn't the best choice?

Cheers!

David

 

P0974 means that the 1-2 shift solenoid CIRCUIT is high. The P0700 means that there is a problem with the transmission; fix the P0974 and P0700 goes away.

My first attempt at repair would be to disconnect the 20 pin transmission connector and clean and inspect all of the pins, then apply some dielectric grease to the contacts. Make sure all of the pins are seated in the connector. Then do the same to the TCM end of the cable. Check for wires burned or chafed. Last would be to replace the shift solenoids, get a quote from a trans shop (guesstimate 6 hours labor + $40 parts).

The P0455 can be anything from a bad gas cap to a bad EVAP vent valve to a hole in the EVAP purge line to a blown fuse (#64 under hood). I would start with easiest/cheapest first; new EVAP vent valve (near the gas tank) part costs less than $20, any dummy can replace.

The only performance difference you might notice is the trans will not "learn" shift points. Presumably that has already been accomplished.

 

I guess he won't be back.
"Thanks. Maybe the Auto Zone gas cap wasn't the best choice? "

Cheers!

 

Thanks. Local tranny repair guy just told me he wants me to leave it for the day, test drive it , scan with pro OBD device.
Thinks low tranny fluid might be the issue.
Does he sound like the go-to guy?

Whaddya think?

 

 

Thanks. Based on what donbrew very confidently said, I'm thinking I should move on to another guy!

 

Tranny fluid level won't affect a defective shift solenoid unless the trans is "bone dry", your ECM picked up on this as a code. Do your research on this.
The guy wants you to leave the car for the day? Yes go to someone else.

 

Most of this stuff is not rocket science. If he's not the right guy, then he shouldn't be working on any cars.