2003 Ford Ranger Edge Surges/revs with AC turned on?

[Earl43P]

Still sounds like you have a bad IAC.

Or, the IAC is trying to compensate, but can't overcome all that unmetered air coming from a vaccuum leak.

Look at all your vaccuum tubes, including the one from the valve cover to the intake. Look for cracks in the plastic tubes and elbows. It helps to manipulate them while the engine is running, listen for an idle change.

 

[shawn25262002]

Just an update. I purchased a new IAC valve from discount auto for $51.98 installed the part and left the battery dissconnected for 30 minutes.

After starting the engine the engine Idle was much higher than it had been since I bought the truck (had the truck for 3 months). I noticed the Idle would settle to about 800 RPm when it used to settle at 500-600 RPM, I noticed when I would put the truck into gear in either reverse or drive that the truck wanted to go on it's own...the RPM would go to 1000-1100 RPM on it's own without even touching the gas...it used to act like it would bog down and hang at 500 or below RPM when in gear and sound like it would stall, I am happy about this but 1100 RPM without foot on the gas seems a bit high?

When I turn the AC on while in park the RPM surges two times to about 1200 RPM then settles to 800 RPM atrleat it does not continue to cycle and surge like it did. It used to want to Idle at 500 RPM then occasionaly dip below and this is when the problems would start with the surging/reving.

Does everything sound like it's good to go?. I want to thankyou all so much for your time and help. I know the forums get alot of clueless newbies like myself asking questions how to fix theyre cars and I sure appreciate all the patience with me.

 

[LearjetMinako]

Sounds like the problem is going away. The PCM will need a few drive cycles to get use to the new IAC.

Just a little FYI:
My Ranger will sit quite well @ 650rpms idle. A/C may cause a surge up to 1,000rpms, but usually no more, with the engine idling.

 

[smokey]

this sounds about right. you will have to run the truck to operating temps a few times for the computer to "learn" how to control the engine.
Once it gets a few 20 minute trips It should learn the idle better.

 

[shawn25262002]

You guys are great, I appreciate it. Just got back driving it a bit more and overall am very happy with it.

If I have one complaint it's the RPM seems to "stick" at 1000 RPM for a few seconds when coming to a complete stop and even when fully stopped which makes me have to use the break a little harder than I am used to.

 

[smokey]

check you linkage to the throttle body and the butterfly it may be sticking a bit.