Engine issues resolved - backfiring, no start, bad idle, etc

[jpipes]

I recently moved from CA to WI. Upon arrival in WI I put the Pinz in storage where it rested for about 16 months while I was back and forth across the country and all over the place.

Before I put the truck into storage it had intermitent issues with stalling, backfiring, rough idle, low RPM at times, and sometimes refusing to start for 10-15 minutes at a time. Just before I put the truck into storage it stopped starting entirely and we had a hell of a time getting it moved. After it's been in storage for a year and a half I decided it was time to get it back on the road. As an FYI this is a well maintainted almost spotless truck purchased from EI in Vallejo CA back in 2006 so it's not like it was hanging on a thread mechanically or anything. It has the electronic ignition conversion upgrade.

When I went to start it up and get it going again yesterday it still wouldn't fire. Nothing. Whirl whirl whirl but no go. Had plenty of gas (flooded the carbs in fact), battery was excellent, and the starter was whirling away. Before diving much deeper I did some reading on the forum here and came to the conclusion that I needed to replace the ignition coil. I had a Petronix coil that EI had installed back in 2006 as a part of the electronic ignition upgrade. Everything I read and experienced seemed to imply it was the coil. This morning I went to a local VW parts shop located 10 blocks from where the truck was stored and bought a Bosch Blue 12v ignition coil for $52. Took me less than 10 minutes to install it in place of the other and...

The truck started perfectly on the first attempt and purred like I haven't heard it purr in a long time! Perfect idle, no backfires, no rough idle, no stalling, nothing. It started on the first attempt each time and runs wonderful. Looks like all along the issues I was seeing (all the way back to 2009-2010 on and off) and the recent issue with it suddently refusing to start at all was due to the damn ignition coil!!! I rebuilt the carbs in 2010 and even that didn't fix the issue, but now it runs perfectly.

Lesson learned. If you attempt to start and have a good battery, gas, and it's whirling away with no go, it's the coil. Replace your Petronix with a Bosch Blue!!

[David Dunn]

As a sidenote. Be sure your ballast resistor is good. Overvoltage to coils will overheat and break them down, and hot restarts are almost impossible. Run the truck for 20 minutes or so and make sure the coil isn't real hot after shutting down. They'll go through only so much heat before they just give up the ghost entirely.

[berger]

Overvoltage to coils will overheat and break them down...

It should be within 17-21 volts at the coil after starting correct?

[David Dunn]

I sold my manuals, so I don't know!
But , that does sound right. unless you're using a 12v coil... then fry some eggs

[Old Warrior]

Hey There jpipes !

Dave's right about the coil(being 12 volt) it'll get hot real quick. Your resorces are correct. I've been able to purchase re-
build kits for the carbs and fuel pumps, mirrors, etc. through my local VW-Dune Buggy supply establishment with lower prices than listed on several Pinz sites.
Just another note; I had the same problem and while trouble shooting the problem, I discovered the new condenser I replaced during the tune-up was bad, BRAND NEW CONDENSER !! Shoved in another new one and the motor purred to life.
Ya Did Good !!

Old Warrior