96 RAM, 360V8, auto.

One day at the drive through it started alternating between idling rough and normal. A little bit of gas seemed to clear out whatever was going on.

A week later, it's driving fine, I park on the ferry, 30 minutes later go to start it and it was BARELY running, 5 second in it started idling like it had some high performance cam in it or like it was firing on 3 cylinders. I couldn't give it throttle to get it to pull out of whatever funk it was in. The throttle made no change in it's idle.

I shut the truck off, started it again and it was running good. just like a computer.

Fuel economy seems to be down dramatically while towing, but seems normalish under no load.

CAT is pretty new. When it was replaced it was rattling, but because the honeycomb came loose in the cat. One big chunk was rattling, not pieces. Figured it may had been bad luck.

O2 sensors are old, but scan tool says they are both good. Only a misfire was detected - ok I knew that. No other codes.

Does anyone have any ideas other than drive it until it codes or dies? I don't have the money to start replacing things randomly, and the dealership isn't goign to be able to tell me anything I don't know already since I can't reproduce the problem.

I need the truck this weekend to move some rock, so I'm hoping someone has seen this before and can help out.

Thanks.

Does your truck still have an EGR valve? I believe Dodge removed them starting in '97, but I can't remember for sure what year they got deleted. I know my '95 had one and my '97 didn't...

Anyway, I have seen an EGR valve idle like you're describing. They have always cleared out and operated fine off idle however so that may not be the problem. You could always disconnect it or block it off to see if it helps...

Also, how old are the ignition system components? My buddy had a Grand Cherokee with the 5.2L in it that did exactly what you're describing. We traced it down to a bad ignition coil wire that had basically disintegrated right at the boot on the distributor cap end where you couldn't see it until you went to pull the wire off.

When was the last time the truck had a good tune up? It might be time to do some regular maintenance and who knows, you might just fix the problem in the process or at least find it.

Truck got new plugs, wires, cap, rotor, etc. less than 10,000 miles ago. They were WAY bad prior to that and I delt with it shortly after having idle issues start up, even then it was nothing like this problem. If I knew half my plugs were worn gapped to .250 I would have done it sooner. :emb: But that was 100,000 miles since the last time I did the job. (distributer is a PITA to get at)

Just went out, fired it up, brought it to full operating temp. Letting it sit for another 15 to see if I can reproduce what happened. Which I doubt.

The coil probably has 100,000 miles on it. contactor was clean and solid..

Scantool showed O2 sensors working like they should, as well as every other sensor. No trouble codes, no pending codes. :madning:

As of now, I'm leaning toward PCM since a classic reboot straightened it all out. But I am a long ways away from deaming it the problem.

I'm no pro, but my 98 was a little choppy. Seafoam cleared it up. You could try cleaning the IAC (Idle air control), or the TPS (throttle position sensor). If you go to dodgetalk.com there is TONS of info there, and people who know tons about these critters. HTH.
Jason

Install a new coil.

BTW - the problem was found around November of last year.

Of all things the battery was dying. It finally didn't start one morning and I discovered 1 cell was bad and another heading that way.

I've been driving it since and not had any of the problems I described above, including where it would just die after blipping the throttle in park.

That was the last autocrap brand battery I will ever buy.