miss, hesitation, stumble, lurch- and other such terms

[jawja jim]

My 92L B6, 2nd gen has developed a miss problem that I'm hoping some one can point me in the right direction. The car runs fine otherwise, cranks immediately every time, and after the miss, hesitation, stumble continues to run fine. It usually does it in lower RPMs, below 2000, and will do it sometimes 2 or 3 times in relatively quick succession. When it does the CEL usually flashes on and then back off with no codes stored.
It seems to me to be an electrical thing. I've had fuel related misses before and this is different. It's as if the key were rapidly turned off and back on and is usually only 1 or 2 misses, then back to normal. I've tried a different coil and ICM, no change.
Any ideas?

[SiliconSoul]

Hmmm... does it smell rich when it does it? Kinda sounds like when my ECT sensor went bad except it threw a code eventually.

[WmWatt]

I'd clean the ignition wires, clean and gap the spark plugs, clean the distributor cap and rotor, and crimp the spark plug wires on a bit tighter. Some people go out at night, start the engine, and look under the hood for sparks.

[Movin]

Along with WmWatt take an old plug, cut the electrode off and lay it on the engine where it can ground. Run the engine with one plug wire at a time plugged in to the big gap plug. Spark testers have some cheap ones that work like the harbor freight ones. Whatever, that will stress test the whole system except the spark plug itself. If any spark misses you will see it. If you have nothing missing and the plugs are new then the fun kind of diagnostics start lol ! Like Silicon was havin..

[jawja jim]

SiliconSoul, I haven't noticed any particular smell associated with these events.
WmWatt and Movin, the plugs and wires are relatively new, 8 months, and the plugs were cleaned and gap set/checked within 3 months, but I'll be opening the disty and checking the cap and rotor. I do have another new set of wires and am awaiting Rockauto disty within a couple of days. I see a trip to HF to use my new 20% coupon.

In the spirit of full disclosure, navdoc101's “Engine shuts down” posted 1 minute after mine, was/is going on with mine, too. If coming to a stop, push in clutch, engine dies unless the gas pedal had last been depressed. If while applying the brake, you tapped the pedal with the side of the foot applying the brake, idled fine. And I do mean “tapped” the pedal. Enough to cause 100 RPM , or just cause a pause in the rate of fall of the tach as you let off the gas. It was never a huge problem as it always happened while the car was rolling so just popping the clutch refired it, tap pedal, life goes on. This had/has been going on for maybe 2 months.
Also the idle has always been steady 750-800, but if stopped right after one of these misfire events, the idle huntsupand down from 500- 1250 or so with the CEL flashing at the low and then surging back up and down.
Thanks for the input, guys.

[jawja jim]

I thought I'd take a minute and post a resolution(hopefully,as I have driven now for a couple of hours without a miss, hesitation, stumble, lurch), as I have been frustrated before when reading old threads that have none. What I found was that the Halloween B6 2nd gen swap made necessary routing the intake right over the distributor and was "temporarily" made secure by wire tying every thing in place to the battery. Since it ran so sweet and me being lazy, temporarily meant "until a problem develops". Couple of weeks back, I had to remove the battery and wire tied it right back as before, but obviously didn't get it as tight as before. So the intake gradually settled down until the edge of the VAF was resting on the disty boot of the number 1 plug wire. I noticed this when preparing to check the cap, rotor and wires as suggested above. I lifted everything and the problem went away, but quickly returned as everything quickly settled back. Installed a second wire tie, tightened the dickens out of them, and all was well again. So I shucked off the laziness and made a proper brace, installed just below the battery tray, and everything now seems to be rock solid(and more permanent). I had always hated the routing as it prevented readily checking disty and transmission fluid level, but now the VAF can be easily removed to access those things.
I am not sure what the "mechanics" of this had to do with the crappy performance and would love to hear y'all chime in.
Now, the contact with the plug boot had made a slight cut all the way though it, but wasn't in contact with electrical bits. I first thought it may have been shorting out to the VAF case, but all testing proved to me that it's electrically isolated, no ground. The plugs, wires, cap and rotor all still look and perform fine. It was apparently the downward pressure on the cap causing the trouble. Opinions?
Sorry to be so "long fingered" with this, but it is a resolution which is sorely missing on many old threads.
On the dying when stopping issue( similar to navdoc101's “Engine shuts down” thread) , which predated the main issue, while I had it all apart I cleaned the VAF and that issue seems to have lessened to the point where a couple of hours driving saw that happen once. Probably would been 10-20 times before.