I have a slant 6 that was rebuilt two years ago in a 60 Belvedere. It was parked for a few years and I have run a couple tanks of fresh gas through it.

When I get to 55-65 it skips a little and kind of runs erratic. It has new plugs and its not a dead skip and it only does it sometimes. It can clean up and run for 30 minutes with out a problem then she does it again. An increase or decrease in throttle does not help but slowing down can clean it up. I don't know how many rpms I'm turning but it is a factory rear end ratio so maybe 2500-3000 she breaks up. The muffler is bad and the fuel is fresh. It does not feel like its starving for fuel but I could be wrong. The wires and inside of the distributer cap look new.


Any ideas??

Are you running points & condenser or electronic ignition? If points, maybe your contact surfaces are gunked up. Check the gap or dwell. Do the plugs give any indication of any cylinder acting differently than the rest?

If these things check out OK, get back & we can shot-gun you more checks. It's hard to see things through your eyes from our side of the internet.

Mike

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Recognized by US Federal Courts as a Fuel Economy Expert!

Water in the Fuel System...??
DD

It is still a points set up. None of the plugs are fouling out or show signs of firing differently. I will have to look at the points tomorrow.

Water in the fuel makes sence to. I put a 20 in her tonight and she was skipping a beat pretty regular after that. Maybe putting fuel in her stirred up crap at the bottom of the tank.

I will check the filter for water and trash and the points. Thanks

I remember my brother cleaning the fuel tank in his '73 Road Runner. He had a pile of "amber" that would over-flow a kitchen scrub bucket.

Mike

_________________
Recognized by US Federal Courts as a Fuel Economy Expert!

Ethanol will combine with the water in the air and sink to the bottom of the tank. It leaves 84 gas octane at the top, crap at the bottom.

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