High idle with no code

Hi and thanks for using 2CarPros. Com.

If the IAC is new and there are no codes, the first thing I want you to check for is an engine vacuum leak. If too much air gets into the combustion chamber, it can cause a rough or high idle. Here is a link that describes how to check for a leak.

Also, here are the directions from alldata for replacing the IAC. Make sure you did it correctly. The attached pictures correlate with these directions. Also, at the end of the directions, you will see a simple relearn procedure that needs done so the computer resets and calibrates the new IAC.

_______________________________________

IDLE AIR CONTROL (IAC) VALVE REPLACEMENT

REMOVAL PROCEDURE
1. Remove the throttle control cable bracket from the throttle body.
2. Remove the canister purge valve.
3. Disconnect the IAC electrical connector.
4. Remove the idle air control valve (2) attaching screws.
5. Remove the idle air control valve.
6. Remove the idle air control valve O-ring.

INSTALLATION PROCEDURE

NOTE: The IAC valve may be damaged if installed with the cone (pintle) extended more than 28 mm (1-1/8 in). Measure the distance that the valve is extended before installing a new valve. The distance from the idle air control valve motor housing to the end of the idle air control valve pintle should be less than 28 mm (1-1/8 in). Manually compress the pintle until the extension is less than 28 mm (1-1/8 in).
1. Install the new idle air control O-ring.
2. Install the idle air control valve into the throttle body.

NOTE: Refer to Fastener Notice in Service Precautions.
3. Install the idle air control valve attaching screws.

Tighten
Tighten the screws to 3 N.M (27 lb in).
4. Connect the IAC electrical connector.
5. Install the canister purge valve.
6. Install the throttle control cable bracket.
7. The PCM will reset the idle air control valve whenever the ignition is turned ON, then OFF. Turn ON the ignition, then OFF.
8. Start the engine and allow the engine to reach operating temperature.

_______________________________________________________

Also, make sure the throttle cable isn't bad, frayed, sticking and there is no damage to the throttle cable bracket. Here are directions for replacement if needed. Starting with picture 9, all pics correlate with these directions. Also, when the throttle is released, make sure the throttle plate is fully closing.

ACCELERATOR CONTROLS CABLE BRACKET REPLACEMENT
REMOVAL PROCEDURE
1. Turn OFF the ignition.
2. Disconnect the accelerator cable from throttle body.
3. Depress the tangs and remove the accelerator cable from accelerator cable bracket.
4. If applicable disconnect the cruise control cable from the throttle lever and accelerator bracket.
5. Unsnap wire harness clip from bracket.
6. Remove the nuts and bolts holding the accelerator cable bracket to the throttle body.
7. Remove the accelerator cable bracket.
ImageOpen In New TabZoom/Print

1. Install the accelerator cable bracket to throttle body.

NOTE: Refer to Fastener Notice in Service Precautions.

2. Install the accelerator cable bracket retaining nuts and bolts.

Tighten
Tighten the nuts to 10 N.M (89 lb in).
Tighten the bolts to 13 N.M (115 lb in).

3. Install the wire harness clip.
4. Connect the accelerator cable into accelerator cable bracket.
5. Connect the accelerator cable into throttle body.
6. If applicable connect the cruise control cable to the throttle lever and accelerator cable bracket.

____________________________________

Let me know if this helps or if you have other questions. Note: Make sure the o-ring for the IAC was not damaged when you replaced the part, and there is no carbon built up in the throttle body where the IAC mounts.

Take care,
Joe