1984 4k - no start

[Bares, Vittorio]

I went out an bought a *real* digital VOM (was using an analog cheapo
unit).

Ran several tests according to my Haynes:
- Measured battery voltage -> 12.54v
- Measured terminal 2 & 4 on the ignition module plug -> 12.34v
- Unplugged multi-plug on the distr. Measured voltage across primary
post on coil while turning ign on - Voltage went to +2-3v then down to
zero within a second or so.
- With the test leads still on the primary posts, put a jumper wire in
the center terminal of the distributor multi-plug and momentarily
touched ground, this showed 3.8v (I could also hear the fuel distr
spraying) Haynes says it should be between 5-6v.
- Then measured the outer leads of the distr multi-plug, they measured
11.54v (Haynes says it should be 5v, but I think that is an error - can
anyone confirm?).
- Measured primary and secondary resistance on the coil - seemed to be
within spec .7 on primary, 3400 on secondary.

I first ran these tests with the borrowed electronics from the running
4k, then ran the tests with the original equipment. Same results.

Except for the low 3.8v - everything looked ok - so, I went ahead a
tried to start the car. Started right up.

Hmm - I thought - perhaps this is heat related? So, I ran the car for a
while, no more than 5min - turning it off, then on again, 3rd time I
tried this - no start. Had to leave to return the borrowed parts so
didn't have a chance to go through the tests again.

When I got back, sure enough it started right up - but this time on the
first attempt of turning it off and on - it didn't start.

I re-ran the tests here are the anomalies I found:
1. W/test leads on the primary posts - there was no build/decay when
turning on the ign
2. w/jumper on center terminal of distr multi-plug, creating a 'break'
did nothing.
3. Outer terminals read no voltage.

Here I suspected a broken wire - tested continuity of all 3 wires going
from the distr multi-plug to the ign control module plug. All were fine.

As suggested by several listers - looks like I'll be ordering an ign
control module.

Huw - do you have a known working coil :)? (just in case the *bad* ign
module had compromised the current one).

Thanks!

Vittorio -
www.BlissRally.com