My idle is too low, no what?

[Darrengotatruck]

Hey gang, I am a new owner of a 97 v6 extra cab. However, I have noticed that when I start it warm the lidle is 500 rpms or less. The other day it got down to 200 rpm' at a stop light and actuallly stalled on me. When I start it cold it idles at arounf 1300 and works fine for the rest of the drive. Any ideas or suggestions as to what is going on would be greatly appreciated.

[BamZipPow]

You could take a peek in yer throttle body and see if it's dirty. It may be sticking so a good cleaning might be in order. Also, I'd check over all yer vacuum lines and replace them if they are cracked or hard. Probably a good tune up would be a good thing...

If those still don't do the trick, you can adjust the idle screw on the throttle body.

[jrock1981]

your idle air control valve is sticking. it is mounted under the throttle body. remove the throttle body and then the iac valve. clean out the inside of the valve with carb clean untell it looks clean. 3.4 right ? this works 99% of the time.

[mdemeglio]

I was all set to rip the IAC off and give it a good cleaning but last weekend I changed my oil and the problem is gone. Not really sure what the connection is but it's like night and day - the only thing I did was the oil change. The oil *looked* okay but it had been 3k miles since I bought the truck and it's hotter than blazes here in NC already so I figured it was time. Turns out the oil that looked ok was thin as water and dirty as hell (it actually looked like normal oil with a good additive package - deep carmel color) - so I was glad I changed it. Don't know why this affected low idle when hot but it used to be very low and shaking (prolly 400 rpm) and now it's right around 650 rpm when hot in drive. Go figure.

[toyomoho]

When cleaning the IAC valve use a cleaner safe for plastics.

[mdemeglio]

I finally cleaned out the IAC on my 3.4L - easy enough to remove it but I'm wondering if anyone has removed the electric motor that actuates the valve or if they are just spraying out the visible part of the valve once it's removed from the throttle body. I removed the IAC and cleaned out the carbon from the exposed openings and put it back on. When I drove it for a while and got it hot, then stopped for a light, my idle went right back to 400 rpm - so either I didn't clean it enough, it needs more than cleaning, or it's something else like a vacuum leak. I'm starting with the last option and will start spraying the vac hoses with carb cleaner to see if there's a line leaking. It may be that the IAC is truly junk but I'm not going to shell out over 200 clams without being positive.

Someone mentioned they hooked up 12v to the IAC and bench-tested it - there's 3 prongs on my IAC so I'm curious which are the correct two leads to connect power to?