F4i Won't Start
 

got cbr F4i for free from some yahoo who I did some work on his RR900 for him. The cbr doesn't run and I downloaded a manual for. It won't start tho if I give it either and try to start it for a minute it will actually catch and fire off. I turn on the key and the f1 light gives me 15flashes which means there is a problem with injector number 4. I have followed the manual and done all the testing and everythign seems to check out. I'm not real sure what I am doing wrong on this and am hoping someone can give me some tips.

Bueller, Bueller?

Well if you've tested the connection and it's not a poor connection, or open or short circuit in the injector wire then the next step is to replace the injector.

MAY also be Fuel Pressure Regulator. Buddy had similar issue. Also check the FI sub harness for bare wires, make sure the connectors are clean, and if that doesnt work, get a new injector (cheaper buying a used throttle body set than new injector).

But even on 3 cylinders with #4 not working, should still kick over easy. Also is the Fuel pump kicking on for about 5 seconds when you turn the bike on? could be poor fuel pressure which would explain why it isnt kicking over well.

So it turns out the ground wire for the injector was broken from the molle connector at the lil brain box. I rewired it and put in a new connector and it starts right up now. It sounds good too, these thins wind up like lil watches.

Now I have a new problem, the guy before me apparently decided to pull out the fuel pump and when he put it back on he broke one of the bolts that holds it down. Obviously torque specs were not their concern. My problem is can this be fixed or does this require a new tank?

I'm really hoping someone can give me some insight on this. I am not fixing a lot of fix info out there on this.

Post a pic, May have a cheap and easy fix for you, I Have an extra set of throttle bocies and they have the injector subharness still pluged in. If thats whats bad i maybe able to sell you the subharness if the mods dont mind, and you live in the us (you pay shipping for small flat rate box)

I actually have the FI working now. It was a bad ground going back to the brainbox.


I do have a broken bolt on the fuel pump tho and it's spewing gas. I don't know if that bolt can be fixed or if I need to replace the tank. Do you have any idea on that one?

I'm sure there is a way to fix it. From looking at the manual the bolts come out of the tank and then you place a nut over them once the pump is in there and tighten the nut to secure the pump. If the bolt itself is broken off, see if you can see how it's held inside the tank. Then remove it, replace it, and find a way to secure it similar to how it was before.

Seeing as how the bolts are welded to the tank and it needs to be perfect. Odds are you just need a used tank since any kinda weld will bump out a little and will not let everything match up properly. How ever you MAYBE able to weld the hole shut, and that MAY work.