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Discussion Starter · #1 ·
Hi all,

Starting to run out of ideas getting my 998S (non-US version) to run.

Some background. I bought it from the previous owner who hadn't ridden it in 5 years. It ran fine when I purchased it. But I didn't want to risk breaking a belt, so after 1 shakedown ride, I did a full big service on it.

Replaced:
Belts
Plugs
Leads
Fuel & Oil Filters
All fluids.

Installed:
Healtech quick shifter
LED indicators and tail lights
Radiator guards and a few other cosmetic bits.

Since then, the bike won't start.

I've double checked the belt timing.
Have good spark.
Bike is cranking over strongly.
Pump is priming and I have good fuel pressure at the injectors.
I've removed the quick shift kit also.
Have tried another ECU.
Tried to start also using jumper leads attached to another running vehicle to rule out battery issues.

Nothing had any effect on my issue.

When I lift the tank, I can see only a small dribble of fuel coming from the injectors when I crank the bike over on the button.
If I apply 12v to the injectors, I get a nice powerful spray. So there's definitely fuel there.

So it leads me to believe it's an issue with the injectors or the electrical circuit?

Does anyone have any ideas?
 

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Discussion Starter · #3 ·
Thanks, I'll check the TPS and CPS now.

No power commander. It's the standard 996R ECU (which I believe was flashed by the original owner to suit the termis, but I've tried the spare ecu too which had the same effect)
 

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Discussion Starter · #5 ·
are the quick release fittings pushed hard into the tank fittings?

fuel pressure?
Yep, no issues there. With the pump primed, I can apply 12v direct onto the injectors and get a nice strong spray, so I definitely have good fuel pressure at the injectors.

When cranking over on the start button though, it's only a dribble out of one of the injectors, then nothing at all. :confused:

Absolutely no idea what's changed or what could be causing it.
 

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i'd be checking the pressure with a gauge while you're cranking it.

if it was ok before, it can really only be something you've done.

is the ecu earthed?
 

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The fuel pump will run for a few seconds , build pressure at the injectors, then stop running until the computer receives a signal from the crankshaft rotation sensor that the engine is turning.

Without a signal, the pump won't restart, so, when the injectors open, the system will depressurize quickly and the fuel will dribble out, no spray/no start.

Check the circuit from the sensor to the computer. You probably disturbed it when you serviced the bike recently.
 

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The fuel pump will run for a few seconds , build pressure at the injectors, then stop running until the computer receives a signal from the crankshaft rotation sensor that the engine is turning.
Sorry, its just a timer in the ecu that dictates the prime. Im not sure why you give advice when you have no clue? The above is completely made up and NOT correct!
Stop posting unless you are dead certain!
 

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I retract my diagnosis because Octane.au says he has good spark, so obviously the computer is getting timing information from the crank rotation sensor. However, as a safety feature to prevent fires after a crash, the computer will shut off the fuel pump if it is told by the crank rotation sensor that the engine has stopped running. So on startup, the pump primes on a timer and then shuts off until it receives a signal that the engine is turning.
 

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I retract my diagnosis because Octane.au says he has good spark, so obviously the computer is getting timing information from the crank rotation sensor. However, as a safety feature to prevent fires after a crash, the computer will shut off the fuel pump if it is told by the crank rotation sensor that the engine has stopped running. So on startup, the pump primes on a timer and then shuts off until it receives a signal that the engine is turning.
Are you testing my joke level? IF so you got me bad, Bastards! Ill find you :D
 

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Discussion Starter · #14 ·
I gave up and took it to a far more experienced mechanic than myself.

He told me it sounded like it was cam timing when he tried to kick it over, but that didn't explain why there's no fuel being delivered.

Anyways, I'll report back once it's sorted.
 

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Discussion Starter · #15 ·
Prognosis is in. Couple of small f*cukups on my part.

Ignition wires to the coils were going to the opposite coils (V to O instead of V to V), and the cam timing was half a tooth out due to me rotating the belt tension roller in the wrong direction when I tensioned the belts..

Mechanic seems to think the poor injector spray is normal at idle. Although he'd never noticed that happening before.

Embarrassing f*uckups. But it's sorted now. I think I was simply too stressed when I was doing the work. I completed the work over the course of a month in my free time, and was contemplating (and eventually did) quitting my job for mental health reasons, and I'd lost 10kg due to illness at the time I was working on the bike. So lots of brain lapses I guess. :-(

Anyways, picking it up this afternoon and should have it back on the road tonight.
 

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Glad you got it sorted out. You are DEFINITELY not the only one to make mistakes like this... don't beat yourself up.

Enjoy riding it.
 

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the direction of the belt adjuster rotation will make absolutely no difference to actual cam timing.

the switched coil wiring will stop it starting though.
 

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Prognosis is in. Couple of small f*cukups on my part.

Ignition wires to the coils were going to the opposite coils (V to O instead of V to V), and the cam timing was half a tooth out due to me rotating the belt tension roller in the wrong direction when I tensioned the belts..

Mechanic seems to think the poor injector spray is normal at idle. Although he'd never noticed that happening before.

... should be on the road tonight.
I've done worse.
 
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