'85 5kST: Ignition/electrical problem...

[quk@isham-research.demon.co.uk (Phil Payne)]

In message <000901bd6119$91cf4ac0$e1b6ba81@loren.iastate.edu> "Loren Porter" writes:

> Is there a small component somwhere that would prevent the entire
> car from starting at all?

Weigh the car.  Divide by four ounces.

If there is no spark at the plugs, check the basic coil connections -
espcially the ground to the inlet manifold.  Do _NOT_ accept apparent
physical robustness - check electrically.  There are splices in the
wiring loom.

Then you need to check the flywheel sensors - peg and teeth - and the
Hall effect sensor on the distributor.  All of these need to work so
that the ECU can work out:

a) The engine is turning.

b) It's turning in the right direction.

c) Which of the crankshaft TDCs is the firing cycle.

Once these are OK, you should get a spark at the plugs.  I have a little
neon/glass thing that plugs into the plug lead of #1 and then connects
to the plug - it makes it very easy to see if the system is trying a
spark.  You should use such a device on the coil output first - it
may be that the system is trying to fire but a distributor fault is
getting in the way.  If the car has been at a garage, this should have
been checked - but you _never_ know.  Remember that the coil output on
these cars is potentially lethal.

Someone else described pulling the codes - that will tell you if it's
one of the above sensors.

Turbos won't start (and won't give any codes) if there's a major leak
in the crankcase/camcover breather system.

--
 Phil Payne
 Phone: 0385 302803   Fax: 01536 723021
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