4.3 Vortec V-6 General Motors distributor and cap problems 

My 1500 van with the 4.3 vortec had this problem. I knocked the screens out and that was 14 years ago. No more problem since then.

Thank you for the video. Very educational and explained thoroughly.

The white powder is no corrosion, it's the plastic core of the cheap replacement terminals. Accel orNGK make solid metal( brass) terminals in their distributor caps. The only other problem withe these distributors wear on the gear and thrust bearing on the shafts. At about 130k to 150k the accumulated wear puts the rotor position out of phase to the primary trigger timing. Since thr secondary circuit is mechanical& the primary is timed electronically off the crank sensor the event occurs out of position and jumps backhand forth. It's most notable at idle with random misfires. If I had to do it all over again I would just replace the distributor, wires& plugs at tune up time every 120k or so. Oh and Icm and coil too.

Mixed up the cap and the rotor when you pointed them out in the beginning. Thanks for the vid though

Excellent video, I’m gonna have to replace the distributor on my 02 blazer ZR2 4.3 soon, I’ve put it off long enough buy throwing new distributor caps at it every couple years. I personally think these distributors were a design flaw from GM, everyone I’ve talked with that owns a 4.3 has gone through this problem lol, i love my old blazer and at least I can work on it.

Drill out the screens and get a moroso shim kit. You want to have 0.010-0.015 end play. The shims take a little fitting. Too much end plan and new cheap rotors leads to the center breaking off. If I lived in a humid area I would add a vent to the cap. It wouldn't be a bad idea to take the cap off and clean it out every year or two.

I have rebuilt about 4 distributors. Up and down movement is always a stopper. Next wire pattern and connection to coil members. Also any insulation always kept. Next MANUFACTURE FLAW CORRECTION.

Could this trigger random missfire? I'm trying to figure this missfire like "forever", new cap, coil, wires, sparks and still P300 ... I will have to check these holes as you show in the video. The distributor is the one from factory and the van has 233k now.

Is there a way to clean that screen, or 2 screens without removing the distributor ? Like a small rubber hose adapted to a vacuum ? I'm thinking of avoiding the problem of needing realignment if / when replacing the distributor after cleaning the screen.

Thanx

around 2:20....is there some measurement for acceptable end play ? Also, is wobble a different problem from end play. ? And can both of those problems be detected by a diagnostic scan of some sensors before taking things apart?

Check the ignition module ....

Can this cause a tapping noise in the engine almost like a bad lifer tick sound

What causes a vacuum leak

Re: those holes @ 1:10 so what am I supposed to do to keep the screens clear ?

Ill never buy anything other than a ac- delco cap...it's the only one i haven't had no starts on humid and or rainy days...