Hey guys, I've lurked on your really cool forum over the past year and gotten some really good information, but haven't been able to find anything concrete on my current problem;

Without any prior symptoms the engine developed a hard misfire/ cut-out usually at 7k rpm and higher (won't really get much more than 8500 rpm now) and the tach swings wildly and rapidly between 4k & 8k.

I've pulled and tugged on all of the wiring from the CDI unit forward to the coils, ignition switch, headlight and start switches and tapped on them all but cannot duplicate the problem independently.

It has to be revved to about 8k in neutral to duplicate the problem, runs absolutely fine up to that point.

It's not a bogging or a slow occurrence so I'm doubtful that it's a fuel related issue or valve adjustment.

I'm leaning towards the CDI since the tach is also affected.

Any advice or input would really be appreciated before I drop a couple bucks on a used one to test my theory.

Thanks

 

Chirp, chirp, haha.

Okay, ruled out the CDI with a known good unit (anyone need one, I have one for sale, lol)

I'm wondering if a worn CCT might allow enough slack in the chain to affect the cam/crank sensor reading causing a poor signal to the CDI? The chain is getting noisy again (replaced the CCT about 10k miles ago)

Any input?

Thanks

 

Found a link to an online shop manual thanks to this forum and figured it out with the wiring diagram; the pulse generator connector at electrical junction box behind the battery had backed out...vibration at higher rpm causing it to lose connection entirely.

Figured I'd post the fix for anyone else that might run into this.

That link to the manual was a lifesaver

 

well done matey!,sorry i couldn't of helped you

 

No worries, intermittent problems are a pita when you can put your hands on it, over the net it's almost impossible. The forum helped me out with that link anyway