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Discussion Starter · #1 · (Edited)
No spark/No start issue

I'm helping a friend of a friend with a no start situation on a 1997 ng900 2.0 turbo, automatic transmission. The car was purchased with a bad head gasket and had a broken rear window. The owners is a motorcycle mechanic and tuner, and he looks to have done a good job on the head gasket, replaced everything that should be replaced, the work was very clean, etc...

After the head gasket job the car started right up and ran fine, but occasionally it would stall and die, but then start right back up as soon as he had stopped and shifted into park or neutral. This happened a few times withing the course of a few hundred miles, then one day happened several times ending with the car at his shop not starting at all. Each time the car stalled there was no check engine light after starting back up.

The car turns over fine, be have grounded the DI Cassette and tested for spark - there is no spark. A known working DI cassette was swapped in - no change, I put his DI on my car, and it works fine. I have him to known good working crank position sensors to try, still no spark. The car appears to be getting fuel, however I did not remember to listen for the pump priming, so I can't be totally sure...but regardless there is still no spark.

Any ideas what else would could cause a no-spark situation? All fuses seem to be in tact, nothing is standing out to me as being wrong under the hood...however I didn't have time to trace all the grounds, although I did suggest that to the car owner.
 

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Have you checked for a potential fault in the harness/wire for the DI? Perhaps a wire was chaffed during the head gasket work and got worse with the driving?

I, of course, have no idea on the pin layout for the DI harness.
 

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Discussion Starter · #3 ·
Interesting tidbit: he just sent me a message saying that he pulled the plug off one of the injectors (#4) to check for injector pulse to confirm they are indeed firing. When he went to turn the car over, it fired up on the other 3 cylinders. He shut it down, plugged #4 back in and it restarted again.

I'm going to tell him to check all the grounds on the head, and if everything there seems fine I'll tell him to start wiggling the harness around while the car is running to see if he can manipulate it in such a way that it cuts out again...still seems odd though.
 

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Discussion Starter · #4 ·
Oh, and I just noticed the thread title :lol:

Spart=spark.

:D
 

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This is Sparta!

Also, neutral safety switch?
 

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Discussion Starter · #6 ·
This is Sparta!

Also, neutral safety switch?
The car turns over fin, i.e. the starter engages and spins the motor round, and round. It just doesn't fire.
 

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The car turns over fin, i.e. the starter engages and spins the motor round, and round. It just doesn't fire.
<-- tard, duhh....
 

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Kinda jumping in a side direction but maybe an ECU problem? Maybe tuner seller tried to tune it and messed up?
 

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Discussion Starter · #9 ·
Kinda jumping in a side direction but maybe an ECU problem? Maybe tuner seller tried to tune it and messed up?
The car is stock, was owned by some lady who didn't have the money to tune it before it was purchased by the guy who owns it now...I highly doubt it has been tuned, or attempted to have been tuned at any point in time. Plus I don't think an programming issue would lead to something intermittent like this.
 

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Discussion Starter · #11 ·
After conferring with an expert, it sounds like it might simply be one loose ground...I'll have the owner trace those and report back.
 

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Discussion Starter · #12 ·
The trouble ended up being that 1 or 2 pins had backed themselves out of the plug/connector part of the DI Cassette harness. He got those pins pushed back in and it has been great since. Very easy fix, once he started wiggling wires around and found the fault.
 
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