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Another No Start Problem.......

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Old 09-11-2012, 05:00 PM
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Dougs951S
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reference sensor stud?
Old 09-11-2012, 05:05 PM
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adrian1
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Originally Posted by Dougs951S
reference sensor stud?
What do you mean?
Old 09-11-2012, 05:06 PM
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Originally Posted by 931guru
Time to take it to a mechanic who knows 944 turbos.
The car has already been at 2.
Old 09-11-2012, 05:11 PM
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Originally Posted by 931guru
Time to take it to a mechanic who knows 944 turbos.
The car has already been at 2.
Old 09-11-2012, 05:33 PM
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there is a stud on the flywheel that is picked up by the reference sensor to give the start signal. It requires a very specific gap of 5 mm from the sensor. If that gap were off or that stud to be missing entirely, the car would have no tach bounce, and of course no fire in the hole.
Old 09-11-2012, 05:38 PM
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Originally Posted by Dougs951S
there is a stud on the flywheel that is picked up by the reference sensor to give the start signal. It requires a very specific gap of 5 mm from the sensor. If that gap were off or that stud to be missing entirely, the car would have no tach bounce, and of course no fire in the hole.
Ok, and the speed sensor does not have set screw or stud for that signal? And both generate 2v from this? Thanks in advance!
Old 09-11-2012, 06:33 PM
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Originally Posted by adrian1
The car has already been at 2 who do not know 944 turbos.
There, I fixed that for you.
Old 09-11-2012, 07:21 PM
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Originally Posted by 931guru
There, I fixed that for you.
thanks
Old 09-11-2012, 07:22 PM
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I will get my hands on an O-scope and check the voltages off the sensors, the stud/screw looks fine...
Old 09-12-2012, 09:02 PM
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What should be the spacing; how much is the reference stud suppose to stick up from the flywheel?
Old 09-13-2012, 12:28 AM
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Well now the fixed the stud and have spark, but the injectors do are not firing. The car also has very high tach bounce, goes up to 1.5k rpm even; as if it was building up to it at certain points. For example it will jump to 400, not go down then 800, then 1200 and go down. I checked both sensors with an o-scope and saw the speed sensor jumping rather quickly and reference much slower which mad sense.

Now why would the tachometer be jumping so high, when it usually just goes to approx 300 rpm? And no injector ground pulse from the DME?
Old 10-20-2012, 02:15 AM
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Originally Posted by adrian1
Well now the fixed the stud and have spark, but the injectors do are not firing. The car also has very high tach bounce, goes up to 1.5k rpm even; as if it was building up to it at certain points. For example it will jump to 400, not go down then 800, then 1200 and go down. I checked both sensors with an o-scope and saw the speed sensor jumping rather quickly and reference much slower which mad sense.

Now why would the tachometer be jumping so high, when it usually just goes to approx 300 rpm? And no injector ground pulse from the DME?
Did you ever figure it out? Having a similar issue



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