Firstly it is quite normal to have the oil gauge flicker at a certain rpm.
This is dependant on the oil pressure and relief valve and spring
characteristics and so is different for every car. Not all do it but many
do. But your oil gauge is electric (assuming North American spec) and so it
is possible that when the engine is bucking and missing it is waggling a bad
connection and causing the gauge to flicker. Is the tach similarly
flicking? If so you have a problem in the ignition LT circuit i.e. ignition
key - white - coil - white/black - points - distributor ground wire circuit.
If not then it is probably HT or fuel. 3k is a bit high but I have
diagnosed HT problems by clipping a timing light on to each plug lead and
the coil lead in turn and watching the flashing as the misfire occurs. If
the flashing gets irregular with the misfire then it is a problem with coil,
rotor, cap or leads. It is also possible that one or more plugs is breaking
down, or though this is more likely to happen with load than revs. If the
HT is regular then it is probably fuel. First step is to remove a pipe from
a carb (watch out for a spurt if the ignition has been on recently), direct
it into a container and switch on the ignition. It should deliver at least
one pint per minute.
PaulH.
----- Original Message -----
From: "joe gorman" <gormanj@ywave.com>
To: <mgs@autox.team.net>
Sent: Saturday, June 26, 2004 4:04 PM
Subject: Problems above 3000 RPM
> ... Around 3000-3200 rpm, the
engine
> would
> seem to miss or buck. I first noticed it in second gear, but it does the
same
> thing in first,
> third and neutral (didn't want to try it in fourth). As I was revving it
in
> neutral, the I noticed
> the oil pressure gauge would bounce about 10 psi. I've never driven the
car
> over 45-50 mph
> or let it rev that high before, so whatever the problem is has probably
always
> been there.
> Below 3000 rpm, it runs fine.
>
> So, what may be causing the bucking or missing?
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