Gino

Could visual observation of a timing light output be used on each plug wire to trouble shoot good electrical conductivity?

Short of a power run, clean shutdown and plug inspection... could this technique help zero in on a candidate?

A930Rocket

I doubt it,

Using an ohm meter to measure resistance would work better.

gsxrken

Gino, if your wires are stock they're 18 years old. Those Beru connectors are a bad idea and they can be really intermittant. What symptoms do you have? I was pulling my hair out with some intermittant misses that would sometimes just be a stumble, sometimes lead to backfiring and barely take gas pedal under load, but run fine at idle??? I even swapped CDI boxes with another 930 owner without effect. Fuel pressures were good, etc. I finally ohmed the wires and one was wide open, and I think at least another was flaky when it got hot. I installed new clewett engineering wires for $130 and new $2 NGK plugs. End of problem.

Gino

OK... I'll drag out the old meter and test the resistance of the wires. Any clue what they're supposed to be? Or, is it a relative thing... all within ~5% of each other? I doubt the wires are original; they look fairly new, but standard in terms of diameter.
Not sure about the Beru connector thing. Do you have a picture of what the original connectors are supposed to look like? I'll take a photo of mine sometime today, maybe during lunch, and post it. Come back and comment if they're the old real deal.
Your description of my surging feeling at steady gas pressure between 2500-3500rpm is right on... like a stumbling. It does not back-fire, nor stumble or hesitate under acceleration.
I did pass HC emissions without being close to the limit less than 2 weeks ago (20 ppm at idle-limit was 50, 150ppm at 2500-limit was 200) so it's not as if I'm having complete ignition failure, just an annoying intermitent stumbling thing. Exhaust tip is dark, but not black, nor is there any soot up my valance and bumber.

Gino

http://forums.rennlist.com/upload/1_plug_wire.jpg

here's a photo of the #1 cylinder plug wire... a Beru?

Tom F

That looks like a stock connector and plug wire. Are you sure that it's a miss that you're feeling?

A930Rocket

Now that I'm thinking about it, if your going to pull and check them all, I would just replace the wires. The time involved not to while your in there wouldn't make sense.

IMHO....

Gino

All-
thanks for your inputs... it was the wires.
not necessarily the Beru connectors, or potential the shields over those wires but certainly because they were old. the wrench said he actual heard arcing when he put his head down in close, and thinks that the complete engine wash down done to 'locate, fix and clean-up my oil leaks' on the service last month, potentially contributed to their demise; and therefore the problem.
so, I'm pleased and it's on to post Turkey Day turbo swapping w/ a K27-7200...
Gooble-Gooble