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I'm praying that one of you fuel injection techies can help me. This is going to be somewhat long so I can describe the problem and the many attempts at a solution. We had just got the bike back from a rebuild and my son and I were out practicing for an upcoming race and the bike was running fantastic. We noticed a few wires that were hanging close to the top radiator hose and decided to tie-wrap them out of harms way. The bike would not start after that. We took the tie-wrap off and the bike started right up and he continued to practice without any problems. I made a mental note that we needed to deal with that issue. A few days later I went out to look at the problem and the bike would not start. We tried and tried and tried but it was not going to start. We checked for spark and that was ok. We unplugged the PCIII and it would not start. It must be fuel so we checked and the fuel pump definitely is working so what can be left. We took out the injector to test it. We held it close to a rag and cranked the bike over and nothing. No spitting, no gas. Just a dead injector. Using a test light we determined that the injector is not getting any signal to fire. After looking at the wiring harness we counted 6-7 splices and I decided that I was going to replace the harness. I don't want to be chasing wiring issues each week at his races. We bought the harness and a new injector (just in case). Replaced both and the bike started on the first push of the button. (ya I know that is unusual for the kawi). It ran great and we shut it off and finished getting it ready for racing. Putting plastics back on and so forth. Loaded it into the toy hauler and away we go for a weekend of racing. That was 2 weeks ago and the kawi has not started since that time. I had a perfomance shop look at it at the race and they told me that the injector must be bad so I purchased yet another one. That didn't work. That injector does not fire either. The one I put in before does not fire. Someone else that had all kinds of electronic testing equipment took a look and he was able to fire the injectors using his equipment and he said that he thinks it is either a bad ECU or a relay. I purchased relays and ECU and plugged them in and guess what. It STILL WON'T START. Yet another person at the race said that you can check the computer codes using the stock dash lights. We read the manual and following the procedure and all we get is one red steady light. There are no codes that match that so we figured there is no code set in the ECU. I am at my witts end. God I hope someone can help. I'm not sure my Kawi dealer has the skill or equipment to debug this.
 

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This is the first i have heard of something like this. As I read the first thing that i thought of was a fuse or the ECU was bad but you said you replaced them and the problem still occurs.... I would check all ground connections. If you have a loose ground wire to the injector it wont fire all the time. But idk i am going to have to think about this one.
 

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First look at the wiring diagram and see which wire should have feed. Need to load test that with a headlight to make sure that circuit can carry a load. Then check the trigger wire, preferrably with a labscope. Good signal or no signal, determines which way to go next. Then check the wire from the injector to the ecm with the headlight to make sure it is not broken or almost broken.

If you have good feed and good signal which I doubt, because the one guy got it to fire. Then the injector would be bad.

You either have a broken wire, almost broken wire, or a trigger/input sensor problem. Can't imagine the spark and injector not picking up from the same crank/cam sensors. But possible as I don't have a diagram in front of me.

Good luck!
 

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QUOTE (Eldridge Performance ATV @ Jun 22 2008, 05:04 AM) index.php?act=findpost&pid=9915
This is a silly question but did you try replaceing the tilt sensor. I had the same problem with a honda cbr600 and I chased the problem all the way back to that. Its worth a shot.
+1 make sure the rollover sensor is still mounted
 
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