I have a 2008 H3 manual transmission 5 cylinder that was giving me the A/C off dash message. From reading on here I found out about replacing the ECT sensor. I did that today and now my AC works again thanks to this forum but on the other hand my idle is out of whack. I cleaned the TB since I already had access to it and used the correct cleaner and replaced the air filter. For example when I put it into neutral coming to a stop sign or stoplight, right before it comes to a complete stop the RPM's shoot up to around 2200 for a few seconds then comes down to normal. Also when driving down the street and I throw it into neutral just to see what happens it stays at 2000 RPM. They should go down since it's not engaged because I'm in neutral.

I did open the butterfly on the TB while cleaning and I've read that maybe I shouldn't have done that? I also tried the re learn trick to no avail and disconnected battery also to no avail. I'm grateful that I have AC now but this problem shows up now of course. I don't know what to do at this point other than cleaning the MAF sensor but I don't see where just cleaning that now would fix my RPM issues but I'll try it. Any ideas??? Thanks.

 

Disconnecting a battery for late model GM vehicles does nothing, they store the last 300 ignition cycles power or no power.

Do not know what the "re learn trick" is?

Moving the Throttle Plate while cleaning is not a big deal, so long as you are gentle.
The proper way to clean a TB is to:
1) disconnect the electrical and EVAP vacuum connectors, remove the 4 bolts and 2) spray it while off the truck. Wipe, let dry, reinstall.
3) When you start the vehicle the first time, do NOT touch the throttle, let it run for 2-3 minutes all by itself so the Throttle Position Sensor can sinc with the Accelerator Pedal Position Sensor and PCM.

Short step #3 and you will have whacky throttle.

I would suggest you redo the clean with it removed the truck on the off chance you displaced some crud into the Throttle Plate pivots and the PCM is over-reacting because of unexpected resistance to smooth movement.

Good luck.

 

If you have a techII or any advanced obd2 device you can reset the throttle body position and it solves it in 1 second.
i once cleaned the throttle body on the alpha and did the proper procedures, from first startup it would shoot to 2500 and stay there, left it for a few mins and no improvement. Drove the truck for 60 miles and zero improvement until I did the reset

 

I ended up removing everything again just to recheck and look at things. What I did was to not tighten the throttle body bolts down as much. It's tight but just a little less than before thinking maybe I smashed the o ring too much? And my idle/RPM's seem to be doing good now. Maybe it was because of that or maybe the computer relearned. Who knows but my A/C went out again on a short trip. Got back in my car and it worked again. And this morning it went out again. Off to the thermostat change now to see if that is the permanent fix. I hope so.

Doc Olds, the relearn trick is just something I saw on YouTube. Sounds like what you explained basically. Start your car and let it run for three minutes. Shut it off for one, then let it run for three minutes again. I tried it but I didn't notice anything actually. Thought I'd give it a shot. I didn't know about not hitting the gas after start up because I did that initially. Maybe that was the culprit? Good advice to know. Thank you! I'll take all I can get.