You write:
> One time a fellow with an XJ6 came into the shop with the following problem.
> The car ran fine at idle, but would misfire badly under hard acceleration.
> Interestingly, it would run fine under hard acceleration, BUT ONLY IF IT WAS
> IN REVERSE, moving backwards.
> What is the explanation?
OK, here's my guess:
The coil was not mounted to the engine block, but, rather to the body
of the car. (This is done to protect the coil from the heat of the
engine -- a wise move.) However, the cable from the distributor to
the coil was a little too short. Thus, the shift of the engine under
acceleration would pull the engine just far enough away from the coil
to loosen the connection, and lose adequate spark.
In reverse, the engine would shift in the opposite direction, and all
would be well.
(Alternatively, the coil could be engine-mounted, and it is the hot
wire to the coil from the wiring harness that is too short...)
Am I even close? I used to have this problem in my '73 Ford Maverick
-- the 302V8 moved around an awful lot on the engine mounts -- at a
rough idle (when playing with the carb), it seemed like the engine was
about to jump out of the car!
--ken
Kenneth B. Streeter | ARPA: streeter@sanders.com
Lockheed Sanders | UUCP: ...!uunet!sanders.com!streeter
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