Need Help Fuel and spark but no start.

[Motogiro]

You may have a problem at the ECU. Carefully check the pins at the plug to the ECU.

 

[patty1104]

After a few months of waiting for Yamaha backordered part, I installed the new Crankshaft position sensor. Still no start, I only had about an hour to tinker with it so thats as far as I got. I should have taken a reading on the new sensor before installing. Either way still no start.

Any resolve on your issue mate? I'm going through the same thing with mine

 

[harpkatt]

Any resolve on your issue mate? I'm going through the same thing with mine

I wish I had more to report. It's below freezing here so not much riding to do. But I hope to get my brother to look at it with me sometime.

 

[robertaustin9177]

It could also be your nuteral safety switch or your kick stand switch I'm going thru the same problem

 

[patty1104]

Tested both of them with no issue found. Tried running on starting fluid and it ran fine. Found that the diaphragm in the fuel pressure regulator was stuck open, so it couldn't maintain fuel pressure besides a kick every now any then after a bunch of priming. part is in the ultrasonic cleaner currently to see if that frees it up, otherwise will have to replace.

 

[kalpetkoff]

Tested both of them with no issue found. Tried running on starting fluid and it ran fine. Found that the diaphragm in the fuel pressure regulator was stuck open, so it couldn't maintain fuel pressure besides a kick every now any then after a bunch of priming. part is in the ultrasonic cleaner currently to see if that frees it up, otherwise will have to replace.

I have the exact same problem. Did you manage to get the bike running?

 

[patty1104]

I have the exact same problem. Did you manage to get the bike running?

Mate it's running like a dream again. The ultrasonic clean broke the regulator free. Otherwise you could just replace it. Something so simple after trying to diagnose for so long. It was done in the shop and all they charged was a couple hours of labour, nothing new required in my case.

 

[kalpetkoff]

Mate it's running like a dream again. The ultrasonic clean broke the regulator free. Otherwise you could just replace it. Something so simple after trying to diagnose for so long. It was done in the shop and all they charged was a couple hours of labour, nothing new required in my case.

Thanks a lot! I will replace mine and I hope the damn thing starts. BTW, I tested the fuel line pressure and it was 36 psi - in specs. I hope it doesn't maintain it, hence, the problem.

 

[patty1104]

Thanks a lot! I will replace mine and I hope the damn thing starts. BTW, I tested the fuel line pressure and it was 36 psi - in specs. I hope it doesn't maintain it, hence

I'm not sure what pressure mine was at during the issue but it couldn't maintain pressure anyways. I had no way of testing at home, they did it while it was in the shop. That's how they found the issue