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Hi All, Just so you won't all feel that I never have any trouble with MY cars, I just thought I'd mention that I had another chapter in a mysterious miss that I had been having since last summer. Last August I got my 69 square out for a month since it had not been on the road for several years. Everything was fine except that it occasionally had problems with missing that seemed to be related to a CD ignition system that I had installed in it. In general it be running fine then it would start to miss and then die completely within 5 minutes. exercising the enable/disable switch on the CDI would always cure it, so I had spent some time trying to fix that unit, but had never really found anything that I could pin down. When it came time to put the 69 away, I transferred the CDI to my 73 square daily driver and continued to drive it with the same occasional problems. Yesterday, however, things changed. The car missed and then died, but exercising the switch would not resurrect it. I finally gave up and just removed the CDI unit entirely and was astonished to find that the car STILL wouldn't start. Okay, I'm lucky, only 3 blocks from home so I walk home and come back later with my daughter and some tools and test gear. Keep in mind that it's about 10F out and there's snow on the ground. First thing: Verify that I really do have spark. I clamp the inductive timing light around the HV coil wire and Laura cranks the starter. No flash from the timing light. Hmmm. Pull the coil wire off the dist and hold it close to ground, crank the starter: Sparks!. Hmmm. Is my timing light broken? Open up the hood of the Ford and try the timing light there. Easy flashes, the timing light is fine. Try it again on the VW, no flashes. Check that I have good 12V to the timing light supply: That's fine, still no flashes. Hmmm.... Check dwell; it's fine. Points look fine. Rotor has the proper 5K resistance from center to end. Go home. Grab an old coil. Pause, Grab an old dist rotor, too. Drive back to the VW. Wire in the other coil: No flash, no start. Starting to get bummed and desperate. Try different rotor. Starts instantly! Whaaaat...? Wire original coil back in. Starts just fine. ???? Okay, I can understand a rotor getting a voltage puncture through that would short the spark to ground in the dist, but that still should have given me a flash from the timing light when I clipped it around the HV coil wire. So what's going on here? Once home I poke inside the rotor with an ohmmeter and find a low resistance spot through the bakelite. I break the rotor in half but don't find the track. So, there's 2 interesting things here: I don't understand why the timing light didn't instantly track down the problem, AND this is the FIRST time in 30 years that I have ever seen a genuine Bosch rotor go bad. BTW, the temp was down to -10F (~-23C) a couple days earlier this week. The car, stock FI and CDI ignition started up instantly. You guys with Webers would have been stuck here 'til March. ;-) Merry Christmas, Happy Holidays, Jim - ******************************* Jim Adney, jadney@vwtype3.org Madison, Wisconsin, USA ******************************* ------------------------------------------------------------------- Too much? Digest! mailto:type3-d-request@vwtype3.org Subj=subscribe