99 Durango Won't Idle on Cold Start

I just bought a new Pacifica and now my 99 Durango (318 with 150K miles) has to sit outside. This morning after sitting outside all night, (temp in the high 30's) it fired right up but wouldn't idle, just kept dying out. I had to start it 3 or 4 times and finally had to keep the RPM"s up in order to keep it running. After 3 or 4 minutes, it picked up and idled fine. I've never had this problem with it before and it's been running great. It didn't flash any fault codes but I'm guessing some type of sensor could be the problem.
Any ideas would be greatly appreciated.

T-bank

Current developments; Problem seems now to ocurr randomly, even when vehicle is warmed up. Based on other similar problem posts, I started out by replacing the idle air control valve, still had the problem. Then replaced the throttle position sensor, same deal. Had about 30K on the distributor cap, rotor and plugs so thought I would replace all that. Haven't had a chance to drive it since, but have started it a few times and idles with no problem. Will keep you posted.

Im kinda having the same problem, did you find out anything else?

Rob:

I forgot to mention that I also replaced the PCV valve last weekend too. The valve rattled when I shook it so it seemed to be OK but I've been driving it to work this week and it hasn't skipped a beat since. I went ahead and replaced the plug wires tonight but I really think the PCV valve was the problem. I've got over 150K miles on the car so I know that I'm getting a fair amount of blow-by from the engine which will probably gunk up the valve pretty quickly. For less than $3.00 for the valve, don't even think about it, just replace it!
Good luck with your problem.

T-bank

OK, thought I had this thing licked. The D has been starting up and running like a champ for about (3) weeks now. I went out to crank it up on Friday and the same old problem, (wouldn't idle, RPM just dropped off to nothing). The only way that I could keep it running was to keep my foot on the gas to keep the RPM's up. I pulled out the Idle Air Control Valve and the thing took off and ran. I cleaned the throttle body again because I thought that maybe there was some carbon and gunk in there that I hadn't got to. It was clean. I put the old IAC valve back in and it wouldn't run either. I checked the voltage output at the terminal pins and it was OK but my Haynes manual says the valve pintle should pull in (open) when the key is turned on. Mine wouldn't move when the key was turned on, only after the vehicle started did it begin to move. I'm guessing the problem must be with the PCM now since the IAC valve wires directly back to it but I gotta confirm this before I go spending that much money on a guess, (the PCM ws replaced by the dealer under warranty around 75K miles). The only thing that doesn't make sense to me is that after it warms up for a few minutes, it idles fine
Any other ideas would be most helpful.

Thanks - T-bank

I think there is a surplus of experts on this board.

OK, thought I had this thing licked. The D has been starting up and running like a champ for about (3) weeks now. I went out to crank it up on Friday and the same old problem, (wouldn't idle, RPM just dropped off to nothing). The only way that I could keep it running was to keep my foot on the gas to keep the RPM's up. I pulled out the Idle Air Control Valve and the thing took off and ran. I cleaned the throttle body again because I thought that maybe there was some carbon and gunk in there that I hadn't got to. It was clean. I put the old IAC valve back in and it wouldn't run either. I checked the voltage output at the terminal pins and it was OK but my Haynes manual says the valve pintle should pull in (open) when the key is turned on. Mine wouldn't move when the key was turned on, only after the vehicle started did it begin to move. I'm guessing the problem must be with the PCM now since the IAC valve wires directly back to it but I gotta confirm this before I go spending that much money on a guess, (the PCM ws replaced by the dealer under warranty around 75K miles). The only thing that doesn't make sense to me is that after it warms up for a few minutes, it idles fine
Any other ideas would be most helpful.

Thanks - T-bank

If you do replace the PCM, NAPA had one that was less than half the dealer cost. From what I remember, you have to give them the approximate miles & get a memory flash done. I believe there are threads on this forum that address PCM memory flashing. Thought I remembered one guy that pulled his PCM, reflashed his memory & put the same PCM back in to fix something. Think it was like $75. Your local part store may be able to recommend somebody for that. I'm not saying that'll fix your problem.

Try a seach under Durango forum: "PCM" or "PCM Flash"

Good luck.

Just an update on the idle problem. I cleaned the throttle body again where the IAC valve inserts just to make sure everything was good and clean. Then I disconnected the battery for a few minutes to (hopefully) reset the PCM. It's been running about a month now without so much as a whimper.
Thanks for the advise on this one.

T-bank

yo, try getting an engine heater, something that keeps the engine at a certain temp so it operates right