SX Viper poor idle, no tach reading, dies on accel.

Took my '03 SX Viper 700 triple out for a ride a few weekends ago. fired up the sled on the trailer to warm up, got it unloaded, but as soon as I hit the throttle to move the sled, it died and I never could get it restarted. Found out the stator was bad. Multimeter would not show a reading from one of the three pins. I replaced the stator the following week with a new one, but the sled was still very difficult to start. It is not the ER model, and I have to pull very hard on the rip cord to get it fired up, and even then it most the time won't want to run at all. Once I got the sled to idle, it was very choppy-like. Sounded like a lot of misfires. lower RPM than usual. if I hit the throttle at all, it dies way below clutch engagement. I also found that the main relay was not functioning. For troubleshooting, I jumped a wire across the relay and now I have power to headlights, instrument gauge cluster, etc. I have a digital readout on the speedo, but absolutely no reading on the tach. It would seem as though the CDI is either not getting a good signal from the flywheel sensor, or is not calculating ignition timing properly anymore. Flywheel sensor is a new part with the new stator, and it ohms out the same as the original sensor (~200 ohms). Any ideas? I'm banging my head against the brick wall with these electrical issues. My suspicion at this point is the CDI, but I don't want to go buy a replacement just to find out that's not what it is.

Maybe the harness rub through problem?

Did you try to bypass TORS?

I bypassed TORS thinking for sure that was the issue but it hasn't made a difference. I started looking for the harness rub through problem, but didn't suspect anything. I assume I was looking at the right harness. There's a bundle of wires that run underneath the engine up to the front of the engine bay, and go up to the headlights and instrument panel assembly. There wasn't any rub through or damage I could see. I also checked the individual wires for any of them grounding out to the chassis and didn't find any issues.

GSOE-sledder said:

I bypassed TORS thinking for sure that was the issue but it hasn't made a difference. I started looking for the harness rub through problem, but didn't suspect anything. I assume I was looking at the right harness. There's a bundle of wires that run underneath the engine up to the front of the engine bay, and go up to the headlights and instrument panel assembly. There wasn't any rub through or damage I could see. I also checked the individual wires for any of them grounding out to the chassis and didn't find any issues.

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The only sure way to check the harness under the motor is to pull it. If it isn't covered in hard plastic convolute, chances are pretty good it hasn't been addressed and should be before spending anymore time or money elsewhere. Every pro-action triple is affected.

OK so here's a bit of an update on what I am seeing. I am trying to focus on the wiring harness that runs under the engine, up to the front of the bay, and then up the hood to the headlights and HUD. I have an aftermarket triple pipe setup that has pretty well melted a section of that harness wiring. It is the removable section that connects near the hood hinge (close to the belt) and then goes up to the headlights, etc. The wire loom, electrical tape, and the wire insulation has burned and melted pretty bad, and I can see a few spots inside where copper is exposed and I am guessing things are shorting out. I'm surprised my headlights still work lol. I am definitely going to try to rebuild that harness with new wire (hopefully I can find all the right colors to keep it original), but I'm wondering if any of you more experienced techs can confirm for me if this is a highly likely reason for the problems with the engine not running right. I'm sure this may have a lot to do with the tach not giving me a reading anymore, that makes sense. But to actually affect the engine?? Anyone experienced something like this that could tell me how likely it is that burned up/shorted wires here would actually affect what seems to be a timing or ignition issue? In the mean time, I think I'll be taking a trip to the electrical supply store

I should also mention that at one point I heard about trying to run the motor with that whole harness disconnected, so I tried that. It didn't seem to make any difference for how crappy the motor was running. It was still difficult to start, it would still die out when I tried to apply any bit of throttle, and it still idled like crap, like it had no power behind it.

The hood harness issue shouldn't affect your engine running. I've had them shorted out and run fine albeit with no lights.