Engine miss on two cylinders

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Apr 27, 2004 | 12:03 AM

etteroc27

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Racer

Joined: Sep 2003

Posts: 275

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From: West Monroe La.

Engine miss on two cylinders

My 72 350 has developed a miss on no. 2 and no.7. I ran a comp. test and have good compression. I have tried two diff. distributors and three caps, new spark plug wires, new plugs, and pulled the intake to check for a vac. leak. I used carb cleaner around the carb base and intake manifold, and can detect no leaks. Everything is tight. I also reset the pre load on the lifters. Nothing has had any effect on the miss. It starts and runs easily, just not on 2 and 7. This has got me baffled. The valves are going up and down and there is fire at the plugs. Any suggestions? Tom

Apr 27, 2004 | 12:30 AM

comp

Team Owner

Joined: Sep 2003

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From: eville in

Re: Engine miss on two cylinders (etteroc27)

double check your firing order

Apr 27, 2004 | 12:57 AM

checklst

Racer

Joined: Apr 2004

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From: Alpharette GA

Re: Engine miss on two cylinders (comp)

I'm with Comp on this one, a few years back I had 2 wires crossed, I was amazed how well it started and ran with 2 cyl misfiring.
:iagree:

Apr 27, 2004 | 07:33 AM

71coupe

Melting Slicks

Joined: Jun 2001

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From: CA

Re: Engine miss on two cylinders (etteroc27)

How do you know it's 2 & 7? I'm guessing the headers are cold. What were the compression readings you took from the cylinders?

Apr 27, 2004 | 07:49 AM

etteroc27

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Racer

Joined: Sep 2003

Posts: 275

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From: West Monroe La.

Re: Engine miss on two cylinders (etteroc27)

The wires are on correctly. I checked that early on. Comp. on the two cylinders is 130#. It runs just as good with the spark plug wires off on these two cyl."s as it does with them on. The plugs are slightly wet.

Apr 27, 2004 | 09:59 PM

checklst

Racer

Joined: Apr 2004

Posts: 271

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From: Alpharette GA

Re: Engine miss on two cylinders (etteroc27)

Check the wires and Dist cap for spark.Do you have access to a plug wire spark light?, I have a old one the it plug into the wire or the dist cap and you can see her fire.. If you have no gas fumes around you can use and old plug and watch it spark but I usually don't like open sparks for safety.

Sorry but thats all I can think of for now!!! :smash:

Apr 28, 2004 | 12:40 AM

etteroc27

Thread Starter

Racer

Joined: Sep 2003

Posts: 275

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From: West Monroe La.

Re: Engine miss on two cylinders (etteroc27)

I used the plug method to check for spark, and seem to be getting a good one. I'm begining to think that it must be some type of mechanical problem, but I don't know what that might be. I'm going to take it apart this weekend. Thanks for the suggestion. Tom

Apr 28, 2004 | 01:16 AM

checklst

Racer

Joined: Apr 2004

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From: Alpharette GA

Re: Engine miss on two cylinders (etteroc27)

If you got compression and spark that leaves FUEL, like you said mechanical maybe the intake valve in not opening allowing air/fuel mixture in,or is sticking and is intermittent giving you compression sometimes

Good luck keep up the good fight you will win sooner or later. :boxing