1994 Chevy Van Inconsistent spark

1994 CHEVROLET VAN
241,000 MILES • V8 • 2WD • AUTOMATIC
Avatar
FERGIE342
  • MEMBER
  • 1 POST
The G30 I just bought (350 w/100k since rbld) makes almost no power. I got passed by a loaded schoolbus off the line this morning, and I'm getting single-digit mpg. I set the timing, replaced filters and bad vacuum lines and read the plugs; they're dry, but a dark rust color in most cyls. I went around the distributor with the timing light and found the aft 4 leads (cyl #7-2-1-8) indicated inconsistent sparks while the others produced a smooth strobe. Changing the cap and rotor had no effect. Is this a camshaft position sensor issue, or something else?

And speaking of timing, the VECI sticker calls for 0-BTC. Does that sound right?

VIN: 1GCHG39K1RF106794

Update: Replaced pick-up coil and ignition module and still have the same problem. In fact, maybe I didn't catch it before, but it seems that all cylinders are skipping. What else would cause this?
Feb 10, 2010 at 5:35 PM
Advertisement
Avatar
2CARPRO JACK
  • CERTIFIED EXPERT
  • 11,533 POSTS
That timing setting sounds right.That engine ( K ) is aTBI unit, they are very solid.Sounds like you may have a module/pick-up coil going bad in the distributor.I would replace both at that mileage, they are both known to act odd at high mileage and fail. That engine doesnt have a cam or crank sensor so the pick-up coil and ignition module are it, much simpler than the newer ones
Feb 10, 2010 at 8:44 PM