Air conditioner causing idiling

[claypwest]

Vehicle: GMC Envoy 2003

Problem:
My air conditioner is causing my RPM's to run real low roughly every four or five seconds. The RPM's run so low at times the Envoy will die. This is happening if I am running the air conditioner or the heater.

Background (not sure if this is related or just coincidence):
The air conditioner has not worked right for some time concerning the controls that adjust it from defrost to blowing from the vents. This also has affected the back air conditioner controls. Once this idling problem started I can no longer get the air conditioner to go off of defrost but now the back air blows without any problems but I have not noticed it getting cold.

Any ideas what would be causing this? Any help would be appreciated!

Thanks!
Clayton W.

[maxwedge]

Welcome to AF. Do you have the automatic or manual system, any check engine lite?

[claypwest]

Thanks, the Envoy is an automatic and there are no check engine lights on.

[maxwedge]

I assume you know I meant whether the controls for the HVAC were the auto type, anyway, I'd start with cleaning the throttle body to try and correct the stalling.

[claypwest]

Thanks and the HVAC is manual, I cleaned the throttle body but I had a "situation" with my wife taking it upon herself to spray substantially more directly into the intake with it attached. Now the vehicle will only start momentarily and dies or won't start at all. Currently I have the resonator off hoping that this will allow the extra intake cleaner to evaporate. Any idea how long I should let it sit and if this does not correct the problem what other options do I have?

Thanks!

[maxwedge]

Once you get it started , take it out and and drive it hard. If no change than a full scan will be the next step. Did you hold the throttle plate open by hand and really clean around the plate and bore of the TB, this is the only way to do this, can't just spray the cleaner in there.

[claypwest]

I did end up taking off the entire TB and cleaning it real good but I think the damage has already been done. The cleaner was sprayed directly into the intake for quite some time. So when trying to start the vehicle I have witnessed that the belts turn but only momentarily and then the vehicle dies. When it starts it makes a turning sound over and over when turning the key quickly but that is it. I am not making any better progress when trying to start it; I am thinking I probably had something fried? I guess if I am out of options I will just go get it scanned as you noted. Would you however have an idea what could have gone out by spraying it like that? I guess if anything this will be a lesson learned and hopefully prevent some other bonehead from going down the same path. Thanks!

[maxwedge]

Many things can cause this, if the engine turns over freely but will not start the throttle position motor may have been damaged, if it will not spin freely on the starter the cylinders are loaded with the fluid, which requires removing the plugs turning over the engine to purge it, I would not suggest any more attempts to start this without expert onsite help. BTW this assumes everything is properly reconnected to the TB.