Why does my engine stall while driving?

Idle is 500rpm with the aircon turned off, when aircon is turned on with engine at idle, idle becomes a little erratic and goes down as low as 200rpm until the aircon controller clicks in and the idle increases to between 700 and 500 rpm.
I cleaned the IAC valve this morning and idle improved, going to test drive now to see if any stall occurs. Will report again later.
Thanks
Barry

Thanks for the previous guidance, I have been for a good test drive around 20 miles, the truck only stalled once when standing still and I shifted into reverse to turn around. Thanks for the tips I think the IAC valve was to blame.
I do have some other issues with the vehicle that I didn't mention before because I didn't consider them dangerous, they all seem to be electrical and annoying that I may have to go to the main dealer to rectify, and "shafted".
1)the internal cab light won't go off after shutting the vehicle down and exiting the cab, I have removed the fuse until I can find the problem.
2) the overdrive switch does not function and the indication light on the dash console does not work.
3) the 4x4 does not engage and the indication light does not show if its on or off.
4) the reversing lights at the back do not come on when reverse is engaged.
All these problems came at the same time and I don't know where to start, can they all be connected? One common relay? One common damaged wire?
Hope you can give me some good pointers where to start solving these issues, as electrical issues stump most people.
Regards
barry

I have a ford explorer 2002 and my truck feel like it want to shut off sometimes I feel like is something with the oxygen but then accelerates and when that is not happening the truck accelerate a little then stops accelerate and stops and keeps going like that.

Feels like no oxygen is getting in, but at times shut off another times it just feels like it will but accelerates itself and when is in parking you can feel when it accelerate by itself, like that for hours is just a little.

Please help :-)

Yes it is also notice that light on it started when the problem started

Car stalls while driving, has happened 4 times in one 50 mile drive, one time when going into a curve I nearly ran off the raod because I din't notice the engine stall cos its quiet until the power steering stopped working.

Yes could easily restart the engine after stalling

My Explorer, stall sometimes when sitting at a red light, it seems to idle too low then dies. Starts fine, runs fine when driving but seems to idle a little on the rough side, it only seems to stall tho when in gear, when it is in park it does not sound to idle right but does not stall.

My explorer only does ths after it warms up, hasnt done it cold yet. The only repair that I have made, about three months ago, was to have the transmission rebuilt. The check engine light is not on either. Thanks

I'm a girl, so dont know much about cars. I need help. My explorer is cutting out and I have changed the egr thingy and changed battery, plugs and plug wires. Whats next?

The check engine light has been on for a while. And no havent changed fuel filter. I had the truck put on one of those plug in things from auto zone, and I thought that was the egr thingy that I had replaced. Does that sound right? But yes the check engine light is on, and didnt change fuel filter yet, is that hard?

Yesterday my lady's 2001 Explorer Sport with a 4.0 SOHC was running like a top and then suddenly after sitting parked for a couple hours it would crank but not start. After letting it sit for an hour or so it cranked and seemed to run ok. She drove a mile or so and it died at a stop light. It wouldn't start for a few minutes and then finally started but in limp mode. The engine was shaking and barely able to idle so she pulled into a parking spot and I came and checked it out and we had to have it towed home. This problem is just out of the blue suddenly with no warning.

Today I was able to get it to start but it shook really badly and was running like it possibly wasn't getting the right air/fuel mixture. There is no check engine light on. At one point today I realized that once it started and was idling horribly and shaking I could press the gas pedal just slightly and hold it there and the rpms would slowly go up and then the engine would smooth out. If I slowly gave it gas I could get the engine up to 3000 rpms and then it would hesitate and drop the rpms back down to 2500. If I try to rev the engine quickly it acts like the engine is flooding or starving and chokes and stalls.

It has 111k miles on it. She has only owned it for 6 months but it has ran flawlessly to this point, other than one random time that it just died at a stop light shortly after she got it.

I'm not familiar with these 4.0L SOHC engines and I'm not really sure where to start. The coolant was low, maybe 1/2 - 2/3 full in the radiator but she said that it did not overheat and she pays attention to her temperature gauge because she's had overheating issues in other vehicles in the past. This coolant has to be going somewhere. Hopefully it's not an intake or head gasket issue. We have not noticed any leaks and the oil was just changed last week and there is no coolant in the oil. The engine doesn't smoke at all either.

Maybe I need to buy a OBD scanner and check the air/fuel mixtures? I recently ordered a cheap ODBII bluetooth dongle for my android phone but the piece of junk only worked once so I have to order a different one. My girlfriend has to work in 2 days and I need to get this figured out ASAP.

Any help is much appreciated.