Q: High idling, jumping while idling, idle air control valve code

asked by on May 24, 2016

I have a car with the check engine light, that came on very recently. There was a code that indicates an issue with idle air control valve. The car has 130,000 miles on it. It has problems with idling. It idles at about 2200 RPMs when it is in neutral or whn parked. The idling is 1200 RPM while driving. The car would jump and jerk during idling while the vehicel is warmed up. It runs as though I am reving it again and again. On one terminal, I found a burnt female plug connecting to the IAC valve. I had the IAC valve replaced but the problem persisits. I noticed the spot where the plug melted at the old valve. It is a spot on the male connector, which is atached to the IAC valve. Is this a connection problem or MAF? What do you think?

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Hi there. This can be caused by the issues that you mentioned or a number of other things. You need to make sure all of the connectors are making good contact. I would then need to know what codes are in the computer to know if this is a circuit issue or not. Most of the time, it is not the circuit but instead a vacuum leak.

If there is a vacuum leak, then the vehicle will act like this and the computer cannot control the idle. Most of the time it is a bad hose or an EGR valve that is stuck open. That is the most common cause for this. I typically remove the EGR to check it to feel the diaphragm on the bottom of it to see if it is moving correctly. If you need to have this repaired, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose and repair your car’s idling issue.

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