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Dies for no reason MSII,COP

Old 08-19-2009, 07:14 PM
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Default Dies for no reason MSII,COP

My cranking rpm is showing less than 100 rpm. I sure think the motor is turning faster than that, but it won't start.

Any ideas what I am doing wrong besides running a supercharger and not a turbo?


msII standalone cops lc-1 93 CAS
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Last edited by Chris Swearingen; 08-19-2009 at 10:30 PM.
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Old 08-19-2009, 07:33 PM
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Looks and sounds a lot like when my battery was low. I'd check that first. If that doesn't work then its likely the supercharger thing.
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Old 08-19-2009, 07:57 PM
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The battery was at 12.5 volts. I assumed that was from cranking and trying to start it. I hooked some jumper cables to my truck and it did indeed start. It warmed up, idled a little high, got to a certain temp and died.

This is going to be fun, but thanks for the help, I am one step closer. At least I think I am.
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Old 08-19-2009, 08:02 PM
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Hm, very odd. I wish I could open your MSQ right now but i'm at work and cant :(

My first guess is that your warmup enrichment is not right for that "certain temp" it died at.
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Old 08-19-2009, 08:37 PM
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You've got a trigger problem.

Here we are zoomed all the way in on one section from your log:



Judging by MAP and BattV, you're cranking continuously throughout most of this frame. And yet RPM is indicated as 0 or 1 throughout most of the frame, with a couple of spikes.

Something is amiss with the CAS, the wiring of the CAS, or the input circuit on the MS.


edit: I just read the bit about jumper cables. Weird. Need a datalog of starting, getting to temp, and cutting out.
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Old 08-19-2009, 09:16 PM
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The forgot to start the log before trying to restart. But the sudden stop is in it.
`
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Old 08-19-2009, 10:04 PM
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I logged it and it did it again. Runs fine and then BAM it just dies.
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Old 08-19-2009, 11:16 PM
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Default it gets stranger

The last two times it died between 7 and 7 and a half minutes into the run.

I just swapped the COPS for the 1.6 L coils and wires and it solid as a rock for 10.5 minutes before I just shut it off.

Is it possible I have the dwell wrong on the coils and they just get warm and shut off?
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Old 08-20-2009, 09:05 AM
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All four coils just crapping out at exactly the same time?

Here's what bugs me- during your initial log, BattV was showing ~11v, yet you weren't getting an RPM signal. That alone is very strange. Now you've got the engine just spontaneously cutting out, presumably with no warning, and yet it only happens on one set of coils vs another?

This is electrical.

What's the power feed to the coils look like? As a diagnostic, I'd consider running a temporary line directly from the battery to the coil supply, and a new ground wire from coils to head. Put a 15A inline fuse in the line. Connect it up just before you start the car, and disconnect it after you turn off the car, obviously. See if that makes the COPs happy.

Oh, how's the grounding cable situation? Should be one from head to chassis by the exhaust, one from PPF to chassis at the back, and of course the one on the battery.
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Old 08-20-2009, 09:14 AM
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In my hollowed out ignitor plug and play world, do I need to disconnect the power from the car to the coils and just run the auxillary power to the coils? I assume the caps can stay in place. The ground for the cops is to one of the valve cover bolts, not the main connection on the back of the head, could that matter?

All the grounds you mention are in place, with supplemental grounds from PPF attachement to back of head using 2awg, and additional ground from head to chassis on intake side.
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Old 08-20-2009, 12:37 PM
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I reduced the dwell to 2 ms and it just idled for 12 minutes before I shut it off and restarted with no problems.

Seems that coil temperatures may have been the issue. I will know for sure after I get it on the dyno tomorrow.
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