Cylinder 4 Won't Fire

[Hunter Jackson]

I have a 2006 hayabusa with 17k....got about 5 miles from home and started sounding funny and fi light came on so I cut it off and back on and same thing so I headed home..got almost home and it cleared up, restarted and no light so I headed back to town and got to the exact same spot as before and it happened again and won't go away....showing code 27.cylinder 4 header cold also...swapped plugs 1-4 no change, then swapped coils no change....12 volts to grey wire at coil...continuity between Ecm and coil plug green wire......no idea at this point I don't have a manual yet so any other suggestions are much appreciated

 

[David Offor]

Can you avoid that route?

 

[Hunter Jackson]

Not following you....do you mean the route I took when I left home? Can't avoid it and I feel as tho I should be able to take any route on my bike with no issues ya know?...I can't really see how that would affect it though...I thought maybe it was bumps on a bridge where it happened both times but I can't find a bad connection anywhere and no wires seem to be shorted

 

[Hunter Jackson]

And correct me if I'm wrong but doesn't crank trigger signal by 4 metal pins passing by a sensor? Like 1 pin for each cylinder?....so if it was crank sensor wouldn't it affect all cylinders?

 

[David Offor]

Sorry, British humour .
If your ckps is faulty, it will give a corrupted signal to the ecu, which in turn, controls the opening duration of the injectors and when the spark happens.
If you have tried swapping coils and plugs, with no effect, try swapping out the injector with no. 3 for e.g.
Do you feel that the bike is underpowered, does it smell like it's running rich, is the temperature normal?
My ckps was faulty and my symptoms were, backfiring through the throtglebodies and moss fire codes on 1,2,3 cylinders, intermittently when I tried pushing it past 9,000rpm, mine also smelt rich and was fouling plugs, also it gave the impression that no. 2 and 3 weren't firing, when I pulled the wire/plugs off of those coils.
Can you check your charging voltage too, rectifiers and regulators play up and so can the stator windings, which give odd running problems but swap out your injectors first.

 

[Hunter Jackson]

I will try swapping injectors first....but from what you say I'm leaning toward crank sensor because it does seem to be rich as I can see gas smoke at times when I had it alittle in neutral and does seem underpowered from previous hayabusa I have been on....for example if I'm goin 20 in 1st and nail it it won't spin the tire and really just kinda dies around 7-8k rpm... this sound like crank sensor? Happen to know how to test it?(gonna search for test on here also)

 

[Hunter Jackson]

Forgot to add that temp always runs right below halfway on guage and charging system seems good...I'm getting like 13.5 volts at 4-5k rpm.....not much over 12 at idle.....correct? And thanks for your replies so far....I'm a decent bike mechanic but electrical is NOT my thing at all

 

[David Offor]

Temp, sounds normal, charging normal, if it smells rich, I'd say the injector is squirting and pumping out unburnt fuel, you have swapped plugs and coils, so, that pretty much eliminates plugs, coils and injectors.
I think there are 3 checks that can be done on the ckps, one of which is a peak voltage test, someone tried explaining it to me but I think I was drunk at the time (it happens) and I think you need a speacial tool made from unicorn horns.
The stator winding is integral with the ckps, Suzuki quoted me £293 but I sourced an aftermarket one for £84, from a company in Cardiff called M&P, it turned my bike back into a rocket.
I'm a diesel/car mechanic by trade but self taught through my own experience on bikes (especially my current busa lol), I'm not great on electrics either but anything can be worked out if you care and are stubborn enough.

 

[Hunter Jackson]

I'm gonna try swapping injectors in the morning if that doesn't change anything I'll just get a whole new stator and try that, I've found them for like 80 bucks also....will let you know if it fixes it for anyone else with this issue...thanks

 

[David Offor]

I'm gonna try swapping injectors in the morning if that doesn't change anything I'll just get a whole new stator and try that, I've found them for like 80 bucks also....will let you know if it fixes it for anyone else with this issue...thanks

I forgot to add, that fuel problems plague busas (mostly the early ones, pump bolted to the back of the engine), a guy in Bristol, that I've lent some parts too, got to the bottom of his running problems and it turned out to be a rusty tank and contaminated fuel, his bike would run for about 10 minutes and then start misfiring, before fitting the ckps/stator, it might be worth flushing your tank and check your pump pressure, just a thought but if it was fuel related, it would more affect no. 1 because it's furthest from the fuel feed but I always like to eliminate things that don't cost money first.

 

[Hunter Jackson]

Ok so when I got bike flasher relay was busted and a key on hot wire was run to orange/white wire which powers coils/fuel pump and other things....was gonna wait till winter to fix until the misfire happened....I didn't know flasher and side stand was on same relay so anyways I corrected wiring and replaced relay and bam she runs perfect....so I guess for anyone with any crazy problems flasher relay DOES make the bike run....and clutch with was also bypassed and wires tied together which had bike thinking clutch was always pulled and that's what was killing my power.....all is well and thanks for the help

 

[David Offor]

Great update, very useful, glad it's all sorted.