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-   -   Crappy idle, misfire on one cylinder. (

DarrenX33 07-18-2018 02:04 AM

Crappy idle, misfire on one cylinder.
Anyone one have any thoughts on this?

Plug 2 is not firing. All others look fine. I tried the following to get 2 to work..

1) plug swap 1 to 2, no change
2) new plug wire, no change
3) tighten up plug, no change
4) change cap, no change
5) change rotor, no change
6) change timing, no variation of timing brings 2 back.
7) change capacitor, no change
8) watched for spark on plug while grounding it. no spark until you hit about 1500 rpm, then spark is there but looks weak. Perhaps my spark is weak all around.

Distributor was just rebuild/restored by Jerry MacNeish. I have new plugs, wires, coil, engine harnesses. Totally stumped.

Mr. Chevy 07-18-2018 03:59 AM

Maybe you have a faulty coil even though its new... Are the points ok??


Woj 07-18-2018 10:56 AM

It seems like the coil is the only thing you have left to change. Maybe swap out the coil for a known good coil? One thing I have found in the past is that most point sets, even the later GM are junk. I was told to give Echlin points a try, I did and really do like the quality of their points. I bought these at NAPA.

Good luck and let us know what you find.

1967 4K 07-18-2018 10:58 AM

Do a cylinder compression check. Could be in the valve train, hope not.

Postsedan 07-18-2018 11:12 AM

This is what I use on all my cars. As Phil said, today's points are junk.
Your very first tow ride home and you will throw away them points.


cook_dw 07-18-2018 11:38 AM

Was it running fine before the distributor rebuild? Swap distributors would be the first thing I'd do if the previous statement was true. If it cleared up then I would send it back. But FWIW its more than likely the points. Local autoparts store used to have points/condenser kit where the condenser was made onto the point plate and they were great. Never had an issue with them. Blue Streak was the name but I wanna say it was owned by Standard Motor Ignition or Products..

L78steve 07-19-2018 12:29 AM

If the distributor was run on a Sun machine and it tested good you can rule the Dist. out as being the problem, points included.

cook_dw 07-19-2018 12:36 AM

Never assume.. You will make an ass out of....... Well you get the point.

As the great President Reagan once said. Trust but verify.

tunes 07-19-2018 12:44 AM

Change the coil. This sounds like a friend's car last year that suddenly wouldn't run. It had a weak spark and would try to start. The culprit was the coil.

Lee Stewart 07-19-2018 01:27 AM

Would the engine experience the same symptoms if either the lifter got stuck or a valve spring broke?

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