Help technical issue

[yamaha1221]

2007 FZ6 Cranks but Won’t Start – Need Help Diagnosing





Hey everyone,





I picked up a 2007 FZ6 from a storage unit, and it’s been a bit of a project. The bike had a ton of wiring issues when I got it—bad splices, corrosion, and random wires everywhere. Since then, I’ve cleaned it up a lot and done the following:





What I’ve replaced/fixed:

• Replaced the main battery wires
• Rewired the ignition circuit (including to the kill switch)
• Cleaned up and properly wired the starter relay (confirmed one wire to battery +, one to starter motor)
• Replaced the intake air temp sensor (old one read 0°C on d:07, now shows correct temp)
• Verified spark on all cylinders
• Verified fuel pump primes and coils are getting power
• Got the injectors freed up and firing into the cylinders
• ECU powers up and displays codes in diagnostic mode

What it’s doing now:

• It cranks strong, fuel and spark are confirmed, and it seems like it’s almost firing
• But it still won’t fully run
• No immobilizer light flashing, and codes have been cleared (d:62)
• All sensors read correctly now in diagnostic mode

I’m wondering if I’m missing something simple—maybe a crank sensor, TPS, or another overlooked sensor? Just want to hear if anyone else has run into something similar. Open to any suggestions at this point.





Thanks in advance!

 

[Gary in NJ]

If you have confirmed spark and fuel, there is only one thing left to check - compression. I'd get a compression tester on each cylinder and check for a minimum of 192psi, with a goal of 220+psi.

 

[yamaha1221]

If you have confirmed spark and fuel, there is only one thing left to check - compression. I'd get a compression tester on each cylinder and check for a minimum of 192psi, with a goal of 220+psi.

Ya I’ll check that next I ordered a new crank position sensor. I retested it and I didn’t own out. At least what I saw it should be 500 to 600 ohms and I was reading that like 236.

 

[Motogiro]

Ya I’ll check that next I ordered a new crank position sensor. I retested it and I didn’t own out. At least what I saw it should be 500 to 600 ohms and I was reading that like 236.

If you have a CPS failure you should see error code 12...

 

[yamaha1221]

I checked the compression and it was fine cylinders 1 through 3 were at 200 cylinder 4 was 205
I’m not sure what to check now really need help. It’s getting fuel and as spark.

 

[yamaha1221]

This is my bike

 

[Motogiro]

Is it my imagination or does this motor sound like there's little or no compression?

 

[yamaha1221]

No it has has compression. I’ve checked it what I’ve noticed today was when I removed the fuse. and tried to start it. It went backfire through the intake, but it does with the fuse in it. I have a check timing and it’s correct.

 

[TownsendsFJR1300]

Are you letting off the starter button as it seems to not turn over smoothly.

Try some starting fluid down the TB's as you crank, see if it fires off..


.

 

[yamaha1221]

no, I’m not letting off the starter thats happening while you’re trying to start it with the throttle cracked or wide open. One thing I figured out was if you pulled the injector fuse and it wasn’t spraying any fuel on the cylinders then that wouldn’t happen and start over fine with using the throttle wide open or just a little bit. Tried using starter fluid to get it started, but it wouldn’t start Tried using starter fluid to get it started, but it wouldn’t start could see combustion in the cylinders. I'm at a loss

 

[Motogiro]

Did you ever get the new CPS installed?
Are you smelling raw fuel?
I'm also thinking if the ECU sees a CPS signal, but the CPS is for some reason is doubling or triple the trigger the ECU might flood the mix.
This could also happen at the ECU. Make sure the ECU plug pins are clean. Also check plugs in the harness. Salt contamination in plugs will reek havoc with cross talk on sensor signals. Rinse suspect plug assemblies with cold water and completely dry with compressed air. Seal with dielectric grease.
This could be a failed ECU.

 

[yamaha1221]

Did you ever get the new CPS installed?
Are you smelling raw fuel?
I'm also thinking if the ECU sees a CPS signal, but the CPS is for some reason is doubling or triple the trigger the ECU might flood the mix.
This could also happen at the ECU. Make sure the ECU plug pins are clean. Also check plugs in the harness. Salt contamination in plugs will reek havoc with cross talk on sensor signals. Rinse suspect plug assemblies with cold water and completely dry with compressed air. Seal with dielectric grease.
This could be a failed ECU.

Yes, I got the new CPS sensor installed. I’ve checked every plug pretty much on the harness. I’ve removed them sprayed them out with electric cleaner than put the electric grease in the plugs.

 

[yamaha1221]

Did you ever get the new CPS installed?
Are you smelling raw fuel?
I'm also thinking if the ECU sees a CPS signal, but the CPS is for some reason is doubling or triple the trigger the ECU might flood the mix.
This could also happen at the ECU. Make sure the ECU plug pins are clean. Also check plugs in the harness. Salt contamination in plugs will reek havoc with cross talk on sensor signals. Rinse suspect plug assemblies with cold water and completely dry with compressed air. Seal with dielectric grease.
This could be a failed ECU.

Yeah, that’s what I’m thinking. It has a bad ECM.