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Old 09-16-2014, 07:25 PM   #1
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Default Ground came disconnected, now I'm a rotary

Driving the other night and the ground loop that normally attaches to the peg right next to the throttle body came loose. Now I can't idle, it's rough with my foot holding steady, like one cylinder isn't firing, really does sound like an angry rotary. Oh, and it's absurdly rich. 8.5:1 at idle and the higher the RPM's get, the leaner/closer to normal I get.

I replaced the TPS, but that solved nothing. What next?

Edit: I have a VVT engine in my 96, but I'm using all factory wiring, except where the cam/crank signal wires for the vvtuner are being run back through the 2 signals wires in the factory CAS wiring, then T-d off so the MS2 and VVTuner get the same NB signals. The pullups in the VVTuner have been pulled out, and the car can run with the VVTuner plugged in. No sync loss except when cranking (31). This problem happens with the VVTuner plugged in or not, makes no difference.
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Old 09-16-2014, 08:01 PM   #2
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You killed a coil, unplug them one at a time to see which one you killed.
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Old 09-16-2014, 08:02 PM   #3
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I'm guessing you have fixed that ground. It's possible that some smaller wire was used as a ground and it has been melted. Check your harness! Or killed a coil...

^
damn it, he beat me to it...
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Old 09-16-2014, 08:15 PM   #4
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I have the FAB9 cops, I pulled them all and used one of the included IK22's to test each coil. Used output test mode and switched the spark plug out of cylinder 1 into all 4 coils, grounding on the head and all sparked.
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Old 09-16-2014, 08:17 PM   #5
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On the side of the VICS manifold now.
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Old 09-17-2014, 12:32 PM   #6
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Fixed - Thanks to Bittetech for suggesting a pinched map line, turned out to be the source. The Denso Iridium plugs I had in (IK22's that came with the FAB9 cops) also got so fouled driving 10 miles at highway speeds that they had to be replaced. Now I'm using NGK E3. Odd design, but they seem to work. I'll start a new thread for VVTuner/Sync Loss issues I'm having now.
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