donbrew

Cellblazers tip about the lower MAP wires is probably it. Well known problem, the sensor wiring connection faces the wrong way (designed for another application) and can rub on the A/C.

RJ_RS_SS_350

Hi Angela, to the forums!!

All of the above, great advice, gotta have those codes! If you have the GMTU (GM Turbo Upgrade) AKA Stage 1 or GMPP, then I would certainly be thinking about what celblazer said about the lower TMAP sensor.

The wire harness can contact the air conditioning components upon acceleration. Some have rotated the sensor 180* to get the wires away from the AC. Some have shimmed the intercooler forward to gain some space.

EDIT: donbrew keeps beating these slow fingers!!!

Angela Moneta Meltinos

Yes, I have the Stage 1! And when I told my DH what you said about the wiring issue with the MAP he said that makes sense. He had to replace the timing chain this past winter (it took him 2 months!) and did the plugs at that time he said. Hopefully this is something he will look at for me. You guys have been so helpful, thanks a ton! He doesn't seem mad at me for asking either.

I really love my car, it's so fun to drive, when it runs well, I just want to run well again.

Oldblue

Fingers crossed he'll get to soon.

firemangeorge

Not to be the pessimist, but that lower TMap wiring is a pain to get at. I hope your hubby is up to laying on his back to work on this. Unless you have access to a lift.
2 things to note. 1.See if you have the old style "crimped on" wiring install or the newer version that had the factory look plug-in harness.
The old style crimps are where most of the problems have occurred. Don't recall anyone posting up problems with the plug-in harness.
2. Most of the people having issues with the wiring rubbing on the compressor have been automatic transmission owners. The 5 speeds seem to have more clearance and seldom rub there.

Oh yeah. CEL numbers. You should get them pulled and post them up. Would hate for you be chasing down the wrong thing if the codes don't indicate a TMap/wiring problem.

Here's a picture of the lower TMap wiring plug(in the red circle). There is also an upper one on the manifold. Disregard the crinkle black plate. Your's won't have that part.

Angela Moneta Meltinos

We do have a lift and it's a 5 speed. He's a bit preoccupied at the moment, just bought a chopper to play with. Sigh...... wish it hadn't gotten so chilly, I'd just ride my motorcycle to work!

Angela Moneta Meltinos

Well he pulled 4 codes off this past weekend, didn't bother to write them down, he's waiting for the light to come back on. He said there's no way to know which code was causing the lurching anyway so he cleared them, and of course it hasn't acted up all week! Sigh.......

Oldblue

We'll sit tight and wait till the CEL lights up and he pulls the codes and writes them down. So you can post them here.

JeramieJJ

T-map probably. I will be making a thread on mine and posting pictures of the worn wires and rusted t-map bolt. All due to rubbing and moisture of the crimped wire from Stage1 kit.

donbrew

If you are replacing the TMAP be sure to follow the HHR specific directions about trimming the tab off. TSB# 09-06-04--009
https://www.chevyhhr.net/forums/prob...d-23231/page4/