Steve,
I've had similar instances in other cars. The usual reason is the engine
is running lean, or retarded and hot, the exhaust valves are cherry red,
and you don't need a spark plug to ignite the mixture still coming in.
Perhaps the retardation? The extra rich gas aids in running on.
Steve
Steve Sage wrote:
>Tigers:
>My Tiger has fairly recently started to sometimes "run on" when I turn
>off the key. In other words, engine running, turn off the ign. key, and
>the engine hesitates to shut off for a second or so, then shuts down but
>kind of runs for a second or two before stopping. If I idle the car for
>10-15 seconds before shutting it down, it's less prone to run on after
>shutdown, but still does on occassion. If I pull into the driveway and
>immediately turn it off, it tends to run on as described. Interestingly,
>this seems to co-incide with the cooler weather now in Los Angeles.
>
>The only two recent changes I've made are retarding the timing a bit so
>it doesn't ping under a heavy load, and adjusing the idle circuit screws
>on my Holley 4Bbl carb (I set them a bit richer than they were, which
>really smoothed out the idle very nicely.
>
>Any ideas on this out there?
>
>Steve Sage
>1967 MK1A
>
>
>
--
Steve Laifman
Editor
http://www.TigersUnited.com
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