Missing when idling???

I can't seem to get my low-mile '99 5.2L 4WD Durango to stop missing at idle when in Drive. Every 5 to 30 seconds, it has a slight shudder when I'm at a stoplight. It is often two slight shudders, back-to-back, a split second apart. There are no trouble codes or indications of a miss-fire code when I had it checked by my mechanic.

So far I've recently replaced the plugs, wires, cap, & rotor; I've added injector cleaner; I've cleaned the throttle body thuroughly including the idle-air control valve; and I performed the TSB which rerouted several of the spark plug wires to avoid cross-firing.

I'm beginning to suspect a bad/severly clogged injector. Does anybody have any ideas?

OK, the plot thickens. Twice in as many weeks the truck would not idle when started. I had to keep my foot on the gas to get it to run. After 30 seconds or so, it would start to even out.

I went out over lunch today and Durango wouldn't turn over. NOTHING - but the clock worked... !%$!@#$ :angryfire:

Wife to the rescue with voltmeter - checked battery voltage. 12.5 Volt. Hmmm... I checked the battery cables. The negative was fine. The positive cable was tightened as far as the bolt would go, but it was still a little loose on the terminal. It sparked a little. I repositioned the cable and retightened the bolt - all seems well. Truck started up immeadiately.

After reading several other posts (while waiting for wife), I noted that several people mentioned resetting the PCM by disconnecting the battery and turning the key on for 20 seconds to clear the memory (drains remaining voltage perhaps?). So, I tried this before reconnecting the battery cable.

We'll see if this solves any of the idling/starting problems.

Nope. Still missing. Has anybody else had this problem with the ocassional miss at idle? Happens both when warm and when cold...

Otherwise, the truck runs great.

Here is the next theory - distributor indexing is off:

http://intense-dakota.com/tips%20and%20tricks%20pages/dodge_dakota_distibutor_indexi.htm

I've also noticed a subtle miss or "bucking" at 1400-1500 RPMs when at 45 MPH and under a light load. This lines up with the symptoms of the dizzy indexing. Next week I'll be scheduling a time to take the truck in. The dizzy was pulled when they replaced my intake manifold gasket...

Has anybody else experienced a distributor indexing problem on their Durango?

It's getting worse, so scratch my theory. I'm beginning to suspect the transmission. Here is somebody else who had the same problem, but he never found the solution:

http://www.automotiveforums.com/vbulletin/showthread.php?t=198302&highlight=transmission

Any Ideas?

For future reference - the problem is solved.

One of the "new" spark plugs was cracked - causing the low RPM random miss :wtf:

The "new" distributor rotor would not seat properly on the distributor shaft, causing it to sit a little high and slightly off-center -causing the miss at 45 mph :newburn:

Just goes to show - start with the basics...

'Stang - Congrats on troubleshooting and solving a difficult and obscure problem.
And thanks for posting the resolution. So many times, folks post the description of some horrendous problem on here, and then never followup and say what the answer turned out to be.
Dave
Westminster, MD USA

That is my hope - to save someone else the headaches of troubleshooting.

I found about three other posts in my searching with this same EXACT problem on various forums. Unfortunately, each person claimed they were getting ready to dump their truck. No solution was ever posted.

This was a very inexpensive fix! Hopefully I can save someone else the time it took us to figure this out.