[Desertxr]

Hi,
I really need some help on an issue that came up. It’s driving me crazy.

*started losing power on a ride. Had to put the throttle to the floor to keep it running, surged a little, then died.
*turns over fine, realized the fuel pump isn’t coming on when key is turned on, it’s supposed to run for 5 seconds then shut off after priming
*fuse good, relay reads good
*checked kill switch, good
*checked ignition switch, good
*pump runs when relay is bypassed
*pump runs when wire going to ECU (#60 on ECU) is sent to ground
*12 volts going into ECU #60
*good spark, turns over fine
*still won’t fire after pump is turned on by going to ground at #60 ECU
*assuming injectors are not working also even with what I assume it has pressure when pump is on

Any idea on what might be causing this?  Not sure how to check if the ECU is running right.  Figured it might be running somewhat right because I’ve got spark when trying to start.  Is there some sort of sensor or something that would prevent the fuel pump from going through the priming sequence when the key is turned on.  I got a manual and can’t find anything on the starting sequence.
Thanks,
Desertxr

[NMKawierider]

First things first. You need to know exactly what..if any..pressure is at the injectors. If low or none, test it just before the fuel filter normally and bypassed. Test it with the gas cap loose. Below is the wiring diagram for your machine. Download it and start tracing back from the pump...but I get the feeling the pump has an issue. Link will expire in 24 hours so download it soon.

https://acrobat.adobe.com/link/review?uri=urn:aaid:scds:US:6daa9f91-c991-434f-9780-97f153b4d0bf

[Desertxr]

Ok, I will look for pressure at the injectors.  Thanks for the diagram . I will let you know the outcome

[Desertxr]

Got lots of fuel pressure at injectors…..

[NMKawierider]

Got lots of fuel pressure at injectors…..

"Lots"...meaning exactly what? Needs to be 40+..something. Manual says. Anyway there is pressure and if it has enough the pump doesn't run...right?

[Desertxr]

Sorry, I don’t have a gauge to measure the pressure.  It sprayed all over the place when I disconnected the line from one of the injectors.  Seemed like a lot of pressure in the line. Pump only comes on when I force it by grounding the line going to the ECU from the fuel pump relay. Was wondering why the fuel pump doesn’t come on automatically when I turn the key on the ignition switch to prime the fuel system.  Any ideas?

[NMKawierider]

If the pump is good and you have tested the pressure switch as good but won't come on with the key, then look to a bad kill switch first as they are not water tight and do corrode contacts but not both sets sometimes. I believe that switch kills the pump and the ignition. Next check the AUX relay and the pump relay coils. Then while at it check connectors. If all checks out try a different ECU.

[Desertxr]

So, it’s running now  while I was waiting on an ECU I kept troubleshooting the thing.  I left the ECU disconnected for a few days and plugged it back in to check some stuff and the fuel pump started running when I turned the key on.  Tried to get it to start and the fuel pump turned off again.  Unplugged the ECU again for 24hrs and plugged back in and the fuel pump started running again.  Got the thing to fire and it sounded horrible.  Like it was missing badly and almost running on one cylinder. Unfortunately, when it died on the trail the first time I was very tipsy and my wife was driving; needless to say I don’t remember how it sounded when it died or else maybe I would’ve gone into the motor in the first place.  A not running fuel pump when the key was turned on sent me down a rabbit hole. I started with checking the valve clearance and both cylinders. Valves were extremely tight on the intake and loose on exhaust.  Put them back to spec when I noticed cylinder 2 timing chain looked really loose. Check timing and cylinder 2 was way out and noticed the chain could skip over the sprocket.  Timing chain tensioner was trashed.  Got a new tensioner, retimed and it fired right up.  The machine still had a not so good tick that was driving me and the wife crazy so I changed the other tensioner and now all is good! So I guess the ECU and I’m assuming the crank positioner had some sort of magical lock that killed the fuel pump so the motor wouldn’t grenade and the only way to reset it was keep the ECU unplugged from the harnesses for 24hrs or longer.  Other moral of the story is if one tensioner goes bad, assume the other is trashed too.  So happy it’s running smoothly again!

[NMKawierider]

At least it's running again. Odd chain of events though.