A couple of months ago, my car did not want to start after i drove it the day before with no problems at all. There was no spark. Pick up coil and high tension coil were good (resistance measurements). Spark plugs and wires are only 2000 miles old. So i decide it had to be the ICM. Because the distributor was probalbly still the original from factory (isolation of wires from pick up coil were not so good and rotor looked a bit rusty) i decided to buy a complete distributor on ebay from 1Aauto. I have to admit it was the cheapest i found, but the car drove fine for months until i started to have this hesitation/stalling when accelerating. It went from bad to worse and now it’s misfiring at idle too. Timing is OK at -10° with tan wire disconnected but when i point my stroboscooplamp at the black underside of the hood i only have a fine regular pulse on the wire from cylinder 1. On all 5 other wires i have a very irregular pulse/light. On the wire from the coil to the distributor is also ok but ofcourse it’s much harder to tell because the frequency is a lot higher. I read on several threads here that these cheap ICM’s only last a couple of months so i decide to buy a AC Delco, but that did not help at all.
I also checked compression and changed the fuel filter to be safe. Alternator tension is ok both dc (14.02-14.04 V) and ac (0.03 V steady to see the rimple faktor on the dc).
I’m all out of ideas now and hate to pay for shipment and taxed of parts i don’t need so any advice is higly appreciated.

 

Just exchanged the plugs and wires from the cylinders 1 and 3, but cylinder 1 stays ok and the others have irregular pulse/light, which means the plugs and wires are ok.

 

check fuel presure just to be sure

 

Well i put back the old rusty distributor with the new ac delco ICM and the car seems to be running like it use to. These v6 have always a little hesistation and when i shift to 2nd gear it sometimes shakes a little bit when giving too little or too much gas but thats what it always did. So what is wrong whith my new distributor? It can only be the rotor or pick up coil (i had already changed out the cap), wright ?
Another question : i still have irregular light pulses with my stroboscoop on various cylinders except no 1. I did the same test with my wifes as good as new ford fiesta 4 cylinder 1.2 L and found the same there. Very irregular pulses on the 2nd cylinder, 1st and 3th were ok, 4th was not reachable. How can this be?

 

You've got a cheap timing light or bad plug wires on both cars...

I will say this. When I was at school a few years back, they had a 2.5L Iron Duke 4 cylinder mounted to a test stand they used for teaching purposes. It didn't run. Upon testing, it was found to have a bad coil and ignition module. So the school opted for a replacement coil and a BRAND NEW distributor. This distributor had dual pickup coils. The engine WOULD NOT run with the upper pickup connected. So we left it disconnected and the engine ran fine until the modified ignition coil power wire terminal broke (the harness used an older coil with different connectors we didn't have access to so we modified standard blade terminals to fit in the coil terminals...).

It might be that the pickup coil signal is incompatible with the other parts of the system. Also, some ignition pickup coils are wired backwards to others... You need to make sure you get the matching module or you will have to switch the wires around in the connector that plugs into the back of the module.

Replace the ignition coil to be safe. Sometimes other problems in the system cause the coil to develop internal shorts to the iron core.

 

Yeah, the timing light was cheap and i was planning on changing the coil next time i order parts. Thanks for reading.