Hayabusa 2000 Ry, Fouling Plugs, Running Very Rough And Rich.

[David Offor]

Hello all
I have a continuing problem with my bike off poor running, black plugs, backfiring through throttelbodies.
I have also found that by removing the coil connectors one at a time, there is not a significant change in revs.
I have changed the fuel pump, had injectors cleaned/checked and now changed, checked fuel pressure/flow rate, changed water temp sensor, checked mechanical engine timing, compression test, changed 3 sets of plugs including one set of iridiums, balanced throttle bodies, changed coils, map sensor is connected to all 4 throttle body vacums, head gasket changed and head skimmed, new rings fitted, oil and filter changed, tried a different ECU from same year bike.
The bike was poorly maintained by previous owner, that ive found out at my folly, oil looked like tar when i orinally changed it, took 3 oil and filter changes to get a decent colour in the oil, i believe he parked up the bike because of the problem that im trying to solve.
I have a new map/maf sensor on the way, i dont know if the cam shaft sensor could cause my problem/s, also i found slight suface corrosion on the small shiny face of the crankshaft sensor pickup, which ive cleaned up with a stone and wet n dry oiled paper.
Im still at a loss for ideas, hoping that a new post might find some new help.
Thankyou in advance. Dave.
P.s ive attached photos of the crankshaft sensor face, i know that this controls when the spark fires, injector operation and the duration that the injectors are open but i get the feeling that my issue is linked to a poor spark, just a thought.

 

[nosbig]

Just wondering, does the bike smoke at all when it is running, could it be excessive blow by causing your plugs to foul? How many miles are on the bike?

 

[David Offor]

Hi nosbig
The bike has 40000 miles, it doesnt smoke, just a very rich smell from the exhausts.

 

[David Offor]

Also, valve clearances are within book tolerances.

 

[sixpack577]

You said that there isn't a significant change in revs if you remove the coil packs individually.
What happens when you rev it with all 4 hooked up?
What about revving it with each coil individually disconnected? Significant/noticeable engine miss?
What did the valves and valve seats look like when the head was off?

 

[Danfaster]

If an Intake air temperature sensor was seeing it as cold out..it would run rich to compensate for the dense oxygen content of what it thinks is cold air? You can measure the resistance with a good Ohm meter. If the specs aren't in the manual you could compare to a known good one.
Process of elimination sometimes involves swapping out for a known good part...lol

 

[Danfaster]

If an Intake air temperature sensor was seeing it as cold out..it would run rich to compensate for the dense oxygen content of what it thinks is cold air? You can measure the resistance with a good Ohm meter. If the specs aren't in the manual you could compare to a known good one.
Process of elimination sometimes involves swapping out for a known good part...lol

 

[David Offor]

You said that there isn't a significant change in revs if you remove the coil packs individually.
What happens when you rev it with all 4 hooked up?
What about revving it with each coil individually disconnected? Significant/noticeable engine miss?
What did the valves and valve seats look like when the head was off?

Hi sixpack577, sorry about my late reply.
When i rev it with all 4 hooked up, there is backfiring, it is uneven with a flatspot below 2500rpm, it clears slightly as the revs climb but always feels like its trying to bog down, with each disconnected, one at a time, im getting flames back through the throttle bodies, i lapped in the valves and used whitespirit to check for leakage when the head was reasembled, which checked out fine.

 

[David Offor]

If an Intake air temperature sensor was seeing it as cold out..it would run rich to compensate for the dense oxygen content of what it thinks is cold air? You can measure the resistance with a good Ohm meter. If the specs aren't in the manual you could compare to a known good one.
Process of elimination sometimes involves swapping out for a known good part...lol

Hello danfaster.
Ive got a feeling i checked the resistance on that sensor a long time ago but i will check it again.
I owned a 99 busa 7 years ago and i seem to remember running it without the airbox on and all it did was bring on an error code but my memorey may be flawed, thanks for the suggestion .

 

[David Offor]

Ive checked the IAT (intake air temperature) sensor and its showing 2.3 k ohms at 20 degrees, so thats ok with the book (2.2-2.7).

 

[David Offor]

Fitted new (2nd hand) map sensor, no change.
Better get back to checking engine timing and valve clearances.

 

[David Offor]

Update:-
Ive now re-checked my valve clearences (exhaust valves on No.2 are very slightly tight) and engine timing the only thing ive noticed is that the arrow 1 that points towards the front of the bike on the exhaust cam is slightly above the upper cylinder head face (dont know if this is relevent), there are 15 pins between the cam shafts on the chain and the arrow 3 on inlet cam is pointing to the 15th pin as per the book.
Could a faulty cam shaft sensor give engine problems? I was told that this sensor either works or it doesnt, is this true????
My next test is compressions and then throttle body syncrinization but ive tried this before.
Any suggestions would be welcome.
Thanks. Dave.

 

[Screwy]

Does sound like your timing is off?

 

[K-Man]

Update:-
Ive now re-checked my valve clearences...

Did you find the cause of the problem?