Idle Speed Stepper Motor Question-Problem Solved

[robfg67]

Idle Speed Stepper Motor - Idle Air Control Valve - Idle Air Controller / I.A.C.

 

I decided to clean the throttle body on my ’89 I-6 engine tonight. During this exercise, I removed the IAC and noticed there was some grime build-up on the pintle. The can of TB spray would not clean all the grime off, so I rubbed the pintle with a clean cloth (to remove the grime) and reinstalled.

 

The Renix manual:

http://www.pirate4x4.com/tech/billavist ... manual.pdf

 

(on page 67) clearly states in the CAUTION paragraph, that if the pintle is removed too far from the motor it will break. Well, I must have done just that because now the engine is idling at 2,250 RPM’s.

 

 

So here is my question, does anyone know of a way to fix this controller or will I be going to Auto Zone in the morning?

[BLHTAZ]

You will be going to Autozone, but you will be lucky if they have it in stock. I checked the ones around here and they all have to order it. The IAC is acctually fairly sensitive and once it screws up, you may be able to play with it and get it working somewhat normal again, but you really need to replace it regardless of what happens now.

[robfg67]

So I installed a new Idle Air Control Valve from Advanced Auto Parts tonight and nothing changed. The engine still idles at 2,250 RPM’s. This is so frustrating-all I did was spray the inside of the throttle body (with TB spray cleaner) and clean the IAC.

 

Can anyone suggest what to look at/fix/replace next?

[maddzz1]

any chance the throttle or cable is stuck.

[robfg67]

No, the throttle cable is fine.

[johngus]

Check the connections of the plug going into the IAC. One may corroded or become dislodged.

[ComancheKid45]

Did you have the TPS off by any chance?

[robfg67]

I adjusted the idle speed screw on the throttle body. You would think that the instructions in the FSM or on the new IAC might mention this step!

[JeepcoMJ]

that probably didn't fix it.

 

check your vacuum lines going to the TB...you probably forgot to connect one

[dragonrider477]

unhook the battery.readjust the stop screw to where it was in the beginning.leave the battery unhooked 1/2 hour to baseline the ecm. rehook the battery and start it.idle should go back to normal.

[robfg67]

I will look more closely at the vacum lines and try the battery disconnect exercise tomorrow. I agree that letting the idle speed screw out seems like more of a "work around".

 

However, with that said, I drove to work this morning (about 7 miles) and she was purring like a kitten at idle-about 600 RPM.