99 Explorer 4x4 runs but won't idle...

[kiwiexplorer]

About 2 weeks ago, drove '99 Explorer (4.0 4x4 XLT,124000 ml) on a very wet day and went through some large puddles with no effect (I thought). Next morning - truck would turn over and run with my foot on the gas, but not idle. Didn't have to floor it - and would run nicely at about 1000 rpm with my foot lightly on the gas - as soon as foot came off - truck dies. After about 10-15 tries - Explorer started and idled fine - off to work I went. Few days ago, I flushed the coolent and sprayed all around the front of engine with hose to make sure I got all old anti-freeze off, started that night with no problem.

Next morning - same deal, light gas foot = goes fine - as soon as I took foot off = truck dies. Only this time it was about 30 mins of trying before it started and idled. Again today - it rained and I have the same problem. Not sure how water/rain is involved but seems to be a common element. Have checked all wires/plugs around engine bay with no obvious exposed/corroded wires. Thought it might be fuel pump, took out fuel pump relay and tried starting - will turn over but wont start at all with foot on gas, so dont think its that. Relay back in, and starts runs fine with foot light on gas. Have read other posts talking about idle problems fixed with new Idle Air Control Valve - will try that next, any other idea's or experiances????

[bmckay]

Next time it happens check the breather/air filter for moisture. It could be starving it for air. If not I would guess a short somewhere which goes away when it dries out. I dought it's the Idle air control valve itself. More likely it's being shorted out by the moisture. Usually sensors either work or don't, but not intermitently unless there's a bad connection or in your case moisture is shorting it out. Just my guess.

[2000XLTV8]

I have the exact same problem - except that mine doesn't involve the water. My 2000 Explorer acts like this all the time. But, like you said, sometimes it runs just fine and other times it won't even idle without my foot on the gas. I'm looking for some suggestions as to what may fix this problem. I've had 3 different mechanics look at it and hook it up to their computers and tell me they fixed it. The same thing still happens and the check engine light stays on all the time. Please reply if you have figured out how to fix it!!! Thanks.........

[limit time]

hey, i have the same problem as the first poster except the engine light doesn't turn on really need help.

regards paul

[john3081]

the puddle makes me think a wet air filter, possibly intake isnt seated properly.
doesnt seem like the fuel pump, sounds more like the fuel injectors to me.

[limit time]

Hey, i figured it out..it was the idle control vave, located on the intake tubes on top of the engine

[nub]

Make sure to check these once in a while to make sure that the tubes don't come off their place. If possible, clamp them somehow so that they don't come off. I had the same problem with a 1993 explorer V6 XLT. I still do check them once in a while since a few seconds of looking it over saves the inconvenience of having your vehicle stuck in the middle of the street.

I don't know if it was related but this happened to me right before I found out that my oil was leaking and the car ran low on oil, then the tubes came off their places.