High speed miss, found with timing light Options

[tradisrad]

Stock FI with Pertronix ingition.

I went to check my timing last night and I noticed that I am having a mis-fire on my #1 spark plug wire. Well at least I think that is what it is. I don't feel anything when I am driving, but the roads are so crappy that I could mistake a bump for a mis-fire.

With the timing light aimed at the fan and the engine at 3.5k rpm my timing light seems to cut out every now and then and I am assuming that the spark is not firing. It also seems to do it at idle.

I pulled the cap and cleaned the rotor & cap contacts and then I pulled the plug wire and found that the area where the plug wire makes contact with the cap had some plastic (from the mold) in it. I cleaned this out (pictures this evening) and reinstalled everything. I checked for the "miss" again and it still was present. I then swapped to the #3 wire I did not notice the "miss".

I am at a bit of a loss on what is going on. Could I have a bad cap, could it be my dizzy?

I can't get back to it until this evening, but I'd like to have some more to go on when I continue to trouble shoot.

[dangrouche]

Stock FI with Pertronix ingition.

I went to check my timing last night and I noticed that I am having a mis-fire on my #1 spark plug wire. Well at least I think that is what it is. I don't feel anything when I am driving, but the roads are so crappy that I could mistake a bump for a mis-fire.

With the timing light aimed at the fan and the engine at 3.5k rpm my timing light seems to cut out every now and then and I am assuming that the spark is not firing. It also seems to do it at idle.

I pulled the cap and cleaned the rotor & cap contacts and then I pulled the plug wire and found that the area where the plug wire makes contact with the cap had some plastic (from the mold) in it. I cleaned this out (pictures this evening) and reinstalled everything. I checked for the "miss" again and it still was present. I then swapped to the #3 wire I did not notice the "miss".

I am at a bit of a loss on what is going on. Could I have a bad cap, could it be my dizzy?

I can't get back to it until this evening, but I'd like to have some more to go on when I continue to trouble shoot.

[dangrouche]

Stock FI with Pertronix ingition.

I went to check my timing last night and I noticed that I am having a mis-fire on my #1 spark plug wire. Well at least I think that is what it is. I don't feel anything when I am driving, but the roads are so crappy that I could mistake a bump for a mis-fire.

With the timing light aimed at the fan and the engine at 3.5k rpm my timing light seems to cut out every now and then and I am assuming that the spark is not firing. It also seems to do it at idle.

I pulled the cap and cleaned the rotor & cap contacts and then I pulled the plug wire and found that the area where the plug wire makes contact with the cap had some plastic (from the mold) in it. I cleaned this out (pictures this evening) and reinstalled everything. I checked for the "miss" again and it still was present. I then swapped to the #3 wire I did not notice the "miss".

I am at a bit of a loss on what is going on. Could I have a bad cap, could it be my dizzy?

I can't get back to it until this evening, but I'd like to have some more to go on when I continue to trouble shoot.

if you are using OEM Bosch plug wires, check that the plug wires are screwed tightly into the plug connector and verify if the little wire that clips onto the top of the plugs is tight. while parked, try to reproduce the high speed miss and push down on the top of the suspect lead and see if it resolves.

[Borderline]

Make sure all the 12V connections on the coil and dizzy are all tight. Check the nuts or rivets on the coil not just the spade connectors. Try running the engine in total darkness. You'll be surprised what you can see. Twice on different cars I found loose connections on the coil that had been giving me all sorts of headaches. FWIW

[904svo]

Check the resistance of each wire from the plug end to the distributor end. I had
the same problem and found the spark plug connector was open to the plug.