krivs399

Hey guys I'm looking for a little help. About 6 months ago I picked up my 5 speed 96 gt convertible. Since the day I got it, it has been idling very very weird. On a cold start it idles just above 2 grand and after it warms up it NEVER goes down under 1,000 rpms. It should idle around 750-800. Since I've had it I've changed the cat's, all 4 o2 sensors, spark plugs, plug wires, ignition coils, filter on the k&n air intake, throttle body, pcv, and some other odds and ends. And yet the car still idles funky. I even checked the throttle stop screw on the throttle body to see if it was holding the throttle open a little. The check engine also comes on and off and my scan tool gives me the code (p1131 ho2s11 snsr indicates lean). Having my car run like this isnt that big of a deal, but id just like to rectify the issues. I was just wondering if anyone had a similar issue before i start ripping everything apart. Any help would be greatly appreciated. Thanks!

07grabber4.0

I'd go back and check over your work. You have done a lot to the engine so go back and check. Maybe one of them needs replacing. But ideling at 2k on a cold start is normal. Doesn't seem like a big issue though

JC316

Check the IAC valve for sure. Lean could indicate a vacuum leak and a large enough one can cause high idle.

caaraa

I'm awesome like that!

96Supedupstang

After warming up your idle should come down, like they said above check your vacuum lines first. If they come back good you may need to get your PCM re-flashed (if you want a stock tune), any ford dealer will do this for a high fee. The person may have bought a tuner for it, and that may have messed something up if they didn't up load their tunes right. If the problem is your computer, you may want to look into getting a tune for yourself, it'll be sort-of close to the cost to get it re-flashed, here in Michigan they want about $150 for it.

krivs399

The car had idling issues befote i added all the aftermarket parts. I forgot to mention i installed a new TPS also. I kno idling at 2k on a cold start is normal but its gone up to 23-2400 at times too. If the idle air control valve wasnt so expensive id just buy it. But theres no returns on electronic parts so i dont want to buy it and have it not fix the issue. I was also thinking that the mass air flow might have some issues. Have any of you guys got that same trouble code? It says snsr indicates lean but doesnt say which sensor.

JC316

Trust me man, check for vacuum leaks and if you don't find any, then it's the IAC valve. Hell, just take it off and clean it, most of the time that fixes it. That or fire the car up and when it wont idle right, take the handle of a screwdriver and hit the IAC a few times, it should drop.

swarthyfellow

I have found that you usually don't need to take it off (IAC valve) just spry some carb cleaner in it and let it sit a bit. Start the car and hit it again but not allot when its running. After that hit it with some WD-40 and it should be good. You may have to do it a few times. I did that to mine and I haven't had any problems over a year and 20K miles.
You also might want to try running some fuel system cleaner. That seems to help out my idle.

uberstang1

get a vacum gauge and verify vacum pressure.