It looks like you've pretty well covered fuel & spark.. What about
compression?
JS
Michael F. Papirtis wrote:
>
> Fellow listers,
>
> Any suggestions welcome!
>
> Have been having a bit of a time trying to find the cause of a miss (or
> pulsing) experienced when backing off the throttle, or holding a steady
> speed. There is also a slight popping from the exhaust as the throttle
> is let off during shifting.
>
> Accelerating has no miss and higher speed cruise has a less noticable
> miss or pulse.
>
> 1980 Spit.
> -Lumenition System and Distributor checked out
> -Fuel pump tests fine
> -Fuel filter has been replaced
> -Coil has been changed out with test coil from other smoothly
> operating,spit.
> -No fouled plugs
> -Plug wires have 1 K on them
> -Timing set to factory specs.
> -Engine, carb, emissions, and exhaust are all at original factory stock
> -Emissions setup includes pump, check-valve, gulp valve, and air rail to
> cylinders
> -No apparent vacum leaks
>
> Any thoughts welcomed!
>
> Thanks!
>
> Mike P
>
> 1980 Spit
> 1979 Spit
>
> "Beat it to fit, paint it to match"
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