E30 start problem - spark coil?

["Vlad" <vlad@xxxxxxxxxxx>]

Dear all.
My BMW is '84 318i with M10 engine. Three days ago I faced with strange problem
- - twenty minutes after stopping the warm engine it refused to start again -
starter spinning, fuel pump making short buzz (as usually) but engine doesn't
start. I was staying uphill, so I slowed down backwards on the level road. and
then engine started normally. Next day on the fifth minute after started cold
engine when shifted on third gear engine stopped without any luck starting it
on the gear again while moving. So I've stopped the car, started engine and
it never stopped until I stopped it. Next day it gone even worse - one trip
without problem - one with stops after every five minutes, sometimes it wasn't
possible to start it - starter spinning, but engine didn't start. I've checked
central cable going from the spark coil (I'm not sure about the terms) to the
distributor - if to unplug one side from the distributor and place it near the
mass (for example on the engine cover) and turn ignition key on the third
position, sometime there is no spark - then, if to plug the cable back again,
engine won't start.
Today I've taken tester and measured low voltage side of the spark coil -
I'm not sure what current there - on the DC it is measuring about 1.2V -
on the AC - something like 6V (I'm not an experienced electrician - so
measuremens could be wrong). I've had not have the opportunity to measure when
engine doesn't start - is any current on the lower side of the spark coil then
But as far as friend of mine is concern - coil shouldn't behave like this -
it aither working or not. Also he noticed two things - it could be something
to do with car alarm system milfunction (I have very basic Excalibur with shock
sensor) blocking some circuits and another - he pointed on the strange behaviour of the
coolant temperature gauge - with key on the second position it showing real
temperature, but if to turn it into third position it going back to zero until
engine started - then it read normally.
There are no experienced BMW electrician here and nobody can give me any advise.
Local BWM dealer came up with stupid answer - "We don't have equipment to test
cars before '86 year"
Please tell me what you think about above problem

Thanks in advance.

Vlad Belov.( vlad@domain.elided )

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