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[kye]

hiya guys.. I crawl back in in need of help again!

I got home in the car, stopped in for a few minutes and the car wouldn't start again. next day it won't start either.

it cranks over healthily, the battery is in good shape. the coil, leads, dizzy cap, rotor arm and spark plugs are all quite new, and have worked fine for a few months.
tests for spark revealed none, and both the ignition on and with it turning over reveal about 2.5V getting to the coil.
so I suspect something in the path between the battery and the coil is faulty, and with a piece of wire, I connect the positive battery terminal and the positive terminal on the coil, and the car starts up first time and runs nicely. I remove the wire and the car continues to run nicely.

so, a mechanical friend of mine tells me there's a relay in the starter motor that routes some power through to the ignition system when it's turning over, but is disconnected at all other times.. he mentions something about the starter drawing all the current down it's lead, starving the ignition of power to spark and start the car.
this theory (while sounding odd with how I view electrical theory) seems to correlate with the experimental results.

a look at the wire diagram didn't reveal any other components that I should look at.

I have recently had an immobiliser put in the car, which I have used for a month or so, but i'm assuming it would be controlling the cars ignition power, so that's an element in there as well.

so, questions:
1) is there a relay in the starter that feeds power to the ignition when it's cranking?
2) are there any fuses or obvious things to check?

it's an 1981 931 UK delivery (which I think is slightly different to the haynes wiring diagrams in some areas?)

all ideas and comments especially welcomed. I have another car as backup, but it's not quite the same!
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it's funny, but when they said "Anything is Possible", that's exactly what they meant....

[MALUKIA3]

Had similar symptoms on my 79 NA. Have no idea if the wiring is the same and I'm certainly no expert.

Believe that the coil gets it's juice from the starter, at least when you tunr the ignition.

In my case, one of the coil leads ran to an ear on the starter and was held on by a screw. it was very difficult to see, but it turns out that while the screw held the lead in place on the starter, the ear that it was attached to was actually broken (the screw held everything together) Occasionally it would break contact just enough for the car not to start and to seem like there was no spark.

Very frustrating and it took me forever to figure it out because it was intermittent.

Don

[red924]

which side is the + on the coil?
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1980 Red 924 CARRERA GT(rep) with custom leather interior + GT goodies!
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[kye]

well, i'd like to say that it's strange when last night she tested OK and then just started without a problem, but I get the feeling that we're all skating on 'intermittent' ice a lot of the time!

yeah, I finally go to fix her and the voltage was good with the ignition on (it wasn't good previously) and she started up first go.

I didn't *do* anything to fix it, except I do have two theories:
1) the relay was stuck and when I started her up the previous time (by jumping the coil to the battery) it jogged it loose again, or..
2) she's a moody one, and got jealous seeing me drive the commodore all the time and fixed herself!

i'm going with the latter!

the positive coil on mine has (from memory) one brown wire and one brown with a white stripe. they're labelled differently in the Haynes (conveniently) but one goes to the positive feed and the other to the feed from the starter (I believe)..

the amusing thing is that she sat there for a week waiting for me to have time to look at her, and then when I do, there's nothing to be done! she probably would have started that whole time...
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it's funny, but when they said "Anything is Possible", that's exactly what they meant....