Questions and Answers
IAC Valve Question
Q. Hello, I have a question about the Idle Air Control (IAC) valve on my 1995 Ford Explorer Sport. It is a 4.0 V-6. I check the resistance through the connectors and it is 9.6 ohms. The book says anything between 6 and 13 ohms is good. I then moved on to check the resistance between one of the connectors and the IAC body like the book said or an internal short.
I didn't get any ohm reading from it. I would assume that means it has an internal short, or that I am not putting my lead on the correct part of the body. The reason I am checking this is because when the engine is running the IAC buzzes quite a bit. Am I checking it correctly? I was wanting to know if I am checking it correctly before I spent $60.00 - $70.00 on a part I may not need.
Thanks for your help,
ScottA. The first part of the test is correct, you did it right and got a good reading. The second part of the test is to determine if there is a short to the body of the IAC. The spec is greater than 10,000 ohms or 10K ohms. If your meter is on the K scale and you are getting a zero ohms reading, it is shorted and needs to be replaced.
If the meter is showing infinite resistance, that is greater than 10,000 ohms and it is good. To be sure your meter is calibrated correctly, touch the two leads together and the meter should read zero ohms. When you separate them, it should show infinity.
To be sure you have a good contact on the IAC housing, touch both leads to the housing about an inch apart and if you get a zero reading, you're good. Keep in mind that you should be checking the IAC with the connector disconnected and directly on the pins of the IAC.
Additional Information provided courtesy of ALLDATA
