Okay, short version of a long story, when the A/C is on it pulls down the idle speed just enough to cause the low oil pressure warning light to come on. Is there a way to adjust the idle speed just a hair to fix this? Most cars I've owned had a solenoid that kicks up the idle when the A/C comes on but this one doesn't or it doesn't work. Any help? Thanks

 

Stickman, try getting yourself a can of throttlebody cleaner and clean out the inside of the throttlebody. Then see what you have at that point.

The idle on our cars is all electronically controlled. So, as you turn stuff on and off, the ECU should adjust the idle accordingly. But, if the throttlebody is sticking a little bit, it can cause what you are seeing.

 

Chris, I'll try that. I'm also changing the oil tomorrow so that may help as well. This lowered idle though started when the dealer installed an unneeded new throttle body a few years back. I noticed immediately that the idle was a bit lower than the original but since there were no other symptoms or side effects at the time I didn't complain. My mistake.
Thanks,
Frank

 

Stickman, you may want to try loosening the throttle position sensor (side near the intake/plugs) and turning it a little bit. this will alter where the car thinks "full shut" is. this may bring up the RPM a little bit. The trick is not to turn it too far or else it may throw a code thinking there is an issue with the TPS.

 

Looks easy enough but which way do you "turn" it? If I loosen the screws and grab onto the plug end do I lift up or push down? Right now it's sitting dead center of the upper slot.

 

Stickman, you want to take the plug end and push it down. take it for a drive and see how it is. If things are worse, then go the other way.

To set it properly, you will need a multimeter. In short, you will need to locate the yellow and the yellow-orange wires (pins 2 and 4) on the TPS sensor plug. Then while monitoring DC voltage and the car in the RUN position (engine not running), you want to adjust the TPS so that the multimeter reads 0.99 VDC (as close to 1.00 VDC as you dare to go, but do not go above). This will make it so that the computer knows where the throttle body is as anything at 1.00 VDC or above makes the ECM think the throttlebody is open part way.

 

Got it! I'm familiar with this process, just didn't have the voltage values.
Thanks