1968 Cutlass, 350 low compression. Drove the car for over an hour yesterday and all was good. Today, backing out of the driveway engine sputtered and quit and won't start. Got fuel going to carb, but no spark. Battery is good and showing 12v, but when I checked voltage at the coil was only seeing 5.7v with ign sw in on position. Distributor has a Pertronix Ignitor (about 18 years old). Is it the Pertronix or the ignition switch I should be replacing?

 

Do you know if the pink resistance wire to the coil was replaced when the Pertronix was installed? It should have been replaced with non resistance wire to get full battery voltage. A bad ignition switch is unlikely, disconnect from the coil and re-check the voltage.

Good luck!!!

 

Yeah, but it sounds like the car was running fine before and now it isn't, with no changes to the wiring.

 

The original Pertronix used the resistance wire along with the current Pertronix I.

 

Based on my experience with Pertronix, that would be the first thing I would look at and throw in the trash. Getting 18 years out of a Pertronix is way better than I did.

 

The engine was running fine until it just died - didn't change any wires. I don't see any "pink" wire, where would that be connected? The Coil has a black wire to the neg terminal and a red wire to the positive terminal. I just put in a new Flamethrower coil that I had in the garage - no start - 5.7 volts at the coils pos terminal.

 

That is what Pertronix did to me and I coasted to the shoulder of the road.

 

I've decided I have a car that just likes to mess with me. Just to make sure I had no spark I got an inline ignition spark tester from Amazon which came an hour ago. With no changes to the wiring I pulled the #1 plug and connected the tester. While I was watching had my wife crank the engine. At first there was no light (spark indication), but after about 10 seconds of cranking the engine fired and the tester light came on. Ran if for about 10 minutes, shut it off and fired it up 2 more times. Not declaring victory until it fires on several consecutive days.

 

Their modulators suck! Dollars to donuts it's the modulator. If you still have a set of regular points throw them in, I bet you it will run fine...... Tedd

 

Unless someone can collaborate that 5.7V (static) is correct for a blaster coil using an 18-y/o Pertronix module and maybe, maybe not resistance wire, that is irrelevant. The symptoms indicate you have either a marginal situation (unlikely since its run this way for awhile), or an intermittent (quite possible in an 18-y/o module). I'm with the others, toss in some points (after verifying a resistance wire is still in play), dial in the dwell and timing and don't look back, or go something factory-reliable like an HEI.