How can you test a 3 wire Idle air control valve

[William Lester]

I have a 2002 Honda Civic with an idle issue “Rough Idle” followed Eric suggestion, took the iac off not all that dirty and has free operation. I’m waiting for a coolant hose (IAC to Block), i will check for vacuum leaks once i get back together

Is there any way to test the IAC

The following are just some things i did:

Tested Wire No.1 Ground (Continuity to Batt Ground)
Tested Wire No.2 12 Volt to Batt Ground (key on engine off)
Tested Wire No.3 nothing

Wire No.1 to Wire No.2: Shows 12 Volts (key on engine off)
Wire No.2 to Wire No.3: Shows 12 Volts (key on engine off)

Connector on IAC Valve:

Provided 12 Volts to No.2 Center

Grounded No.1 No results

Grounded No.3 Valve open

Topic

[college man]

see if this helps.

http://www.justanswer.com/volvo/2f4ka-check-idle-air-control-valve-bad.html

[William Lester]

i found that earlier its a little confusing because there is no resistance reading between any of the pins however if i apply voltage to the center pin and ground the signal pin i can make the valve open and close

Thanks

[William Lester]

Got my new hose today, i cleaned and re-installed the IAC Valve, i made sure to bleed the cooling system, I was ready with my plan to find the cause of the rough idle. I was going to pinch off the PVC hose, i was then going to pinch the fuel return line hoping to increase pressure, I was ready with my brake cleaner and fire extinguisher to look for any vacuum leaks.

To my surprise when i started the car, it went straight to high idle (Cold in Pittsburgh), upon coming up to temperature the idle dropped. As of now this is the best this car has ever idle since I’ve owned it. I have driven it about 5 miles so far.

Thanks

[college man]

Glad the problem is being resolved. 🙂

[William Lester]

Me too, so far so good, put another five or six miles on yesterday, thanks for your input.

[college man]

[quote=”WJL” post=126112]Me too, so far so good, put another five or six miles on yesterday, thanks for your input.[/quote]

Anytime. 🙂

[Author]

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