Idle Problem. Town & Country Van

[scottchalmers]

I have a 1996, 3.8 L Chrysler Town & Country van. 209,000 kilometers. I have just obtained this van, and it has an idle problem that the revs stay around 2000, and when on the road when the odometer is showing speed, it idles at about 3000 rpm. But when the odometer goes to 0, the revs drop to 2000 rpm again.
The battery was just changed. The radio does not work, and the power locks do not work. (They used to). Are these problems related.....
Thanks. Scott

[RIP]

The Idle Air Control (IAC) valve is self desciptive. It's located on the throttle body. Sounds like in your case the valve is stuck open. It either needs to be cleaned or replaced. http://www.autozone.com/az/cds/en_us...rInfoPages.htm Click the images to blow them up. Are you seeing a service engine light?

Are the door locks dead from both the key fob and the switches on the door? If yes, check the two fuses, one on the junction block under the dash and another in the Power Distribution Center (PDC) next to the battery. This could be a Body Control Module (BCM) issue so try pulling the IOD fuse in the PDC for a minute or so. This will reset the BCM. This will only help if the door locks failed after the battery was changed. Disconnecting the battery also resets the BCM.

[scottchalmers]

Originally Posted by RIP

The Idle Air Control (IAC) valve is self desciptive. It's located on the throttle body. Sounds like in your case the valve is stuck open. It either needs to be cleaned or replaced. http://www.autozone.com/az/cds/en_us...rInfoPages.htm Click the images to blow them up. Are you seeing a service engine light?

Are the door locks dead from both the key fob and the switches on the door? If yes, check the two fuses, one on the junction block under the dash and another in the Power Distribution Center (PDC) next to the battery. This could be a Body Control Module (BCM) issue so try pulling the IOD fuse in the PDC for a minute or so. This will reset the BCM. This will only help if the door locks failed after the battery was changed. Disconnecting the battery also resets the BCM.

Hello. I have tested the IAC valve by removing a vacuum hose to see if the revs speed up. They did. So, would that mean that the IAC valve is OK.... When the engine is idling I think I hear an air leak, but I am not sure over the noise of the engine. If there is an airleak could it be that it is causing the engine to compensate for the vacuum loss....

Asd for the radio and locks, I changed fuses etc...and still no luck.

[RIP]

If you hear an RPM change when you turn on the A/C or when you disconnect the connector from the IAC, it's an indication it is working. Can't say for sure about your "vacuum test" but it might make sense. Best way to test it is with a scanner with component testing features. Check with Autozone. They do free scanner testing. Not sure if they have advanced scanners.

Yes, the noise you're hearing could be a vacuum leak and it can bump up the idle. Many time folks will perform maintenance and either accidently disconnect/break or forget to reconnect a vacuum line. Can you find out if any maintenance was done just before this idle cropped up? If yes, look in that area. If you haven't, I would inspect all the vacuum lines under the hood for anything obvious. If that doesn't work, an old trick is to take a short piece of garden hose, cup one end to your ear, then go around the engine compartment to pinpoint the noise. It's a poor mans stethoscope and in this case the ideal stethoscope.

If none of this gets you anywhere try cleaning the throttlebody with a spray throttlebody cleaner. Clean the IAC port while in there. I will assume you are not seeing a service engine light.