GSXR 750 - Fuel injection light & won't accelerate

[Snorty]

So the problems begin

I was out in the GSXR 750 today, and the fuel injection light came on - seemed ok. Then I noticed when I accelerated up to high revs and backed off again - the throttle wouldn't respond at all for a few seconds, then would suddenly start working again, same for changing gears. It seems to be when I chop the throttle it stops working.

No problems at all before this, just suddenly started happening today

Any ideas what this could be?

It's not bogging down or anything like that - the throttle literally just does nothing, so the engine slows down, then the throttle will respond again.
____________________
Current: Yamaha FZ1 '07 | GSXR 750 SRAD

Past: CB125TDC | TZR125 | GPZ500 | CBR600F3 | ZX9-R | GSXR1000 K4

[P.]

Mine did similar, turned out to be one of the injectors. The wire leading to it was frayed and kept shorting!

[Fisty]

Does it bring up a fault code?
____________________
Quietly and consistently taking the piss.
TL1000R | Hayabusa | ZXR400 | TL1000S | Bandit 400 V
Fatter and faster than Fret

[Snorty]

No it just says "FI" on the dash where the temperature should be.

It starts up fine, runs as it should, but if I accelerate up to say, 7000rpm, then just close the throttle, the throttle will just not respond to anything and the bike will slow, then the FI light will come on and stay on.

If I just crawled around at 4,000rpm it would be fine, but anything around 7 or above and the FI light comes on.
____________________
Current: Yamaha FZ1 '07 | GSXR 750 SRAD

Past: CB125TDC | TZR125 | GPZ500 | CBR600F3 | ZX9-R | GSXR1000 K4

[P.]

FI means it has a fault code.

You'll need to honk it into dealer mode, a quick google will tell you how, mine was 2 pins near the rear light.

My guess is the secondary valve thing that usually goes wrong.

[Fisty]

Not sure if the fi system is the same as the tl, but the TL brings up a fault code on the speedo.
Have a look under the LHS of the tail fairing (just lift the seat up) Do you see a plug with a blank in it? If it has short it out with a paperclip, turn on the ignition and it should give a fault code on the dash.

GSXR Fuel Injection (FI) Code List:

C14 - THROTTLE POSITION SENSOR
C15 - ENGINE COOLANT TEMPERATURE SENSOR
C21 - INTAKE AIR TEMPERATURE SENSOR
C22 - ATMOSPHERIC PRESSURE SENSOR
C23 - TIPOVER SENSOR
C24 - IGNITION SIGNAL #1
C25 - IGNITION SIGNAL #2
C26 - IGNITION SIGNAL #3
C27 - IGNITION SIGNAL #4
C28 - SECONDARY THROTTLE VALVE ACTUATOR
C29 - SECONDARY THROTTLE POSITION SENSOR
C30 - SECONDARY THROTTLE CONTROL UNIT
C31 - GEAR POSITION SENSOR
C32 - INJECTOR SIGNAL #1
C33 - INJECTOR SIGNAL #2
C34 - INJECTOR SIGNAL #3
C35 - INJECTOR SIGNAL #4
C41 - FUEL PUMP CONTROL SYSTEM
C42 - IGNITION SWITCH SIGNAL
C46 - EXHAUST CONTROL VALVE ACTUATOR (01-02 1000 and 06-07 600/750/1000 ONLY)
____________________
Quietly and consistently taking the piss.
TL1000R | Hayabusa | ZXR400 | TL1000S | Bandit 400 V
Fatter and faster than Fret

[P.]

My bet is 28/29/30

[Old Git Racing]

Go on the Gixxer forum and there is a sticky all about FI problems and how to id them.

OGR
____________________
2022 Tiger Sport 660 2019 Street Twin 2003 K3 gixxer 1000 1998 Srad 600 track hack

[Snorty]

c00 - no fault apparently!
____________________
Current: Yamaha FZ1 '07 | GSXR 750 SRAD

Past: CB125TDC | TZR125 | GPZ500 | CBR600F3 | ZX9-R | GSXR1000 K4

[P.]

[Snorty]

Bizarre - I got it into dealer mode but the FI light wasn't on as you said, so c00 was showing.

Now I took it up the road with the dealer mode still engaged, usually it messed up right away, and starts being irritating. So I gunned it up the road, running fine, then about a mile later, it does it.

C24 and C25.

What could this mean?
____________________
Current: Yamaha FZ1 '07 | GSXR 750 SRAD

Past: CB125TDC | TZR125 | GPZ500 | CBR600F3 | ZX9-R | GSXR1000 K4

[P.]

Something is pissing around with the ignition side of stuff...

Unsure how you check ignition signal.

[Snorty]

I can only think perhaps it's a wiring fault somewhere - the bike pulls hard and strong, it's just when I back off the throttle, the engine dies instantly, pull the clutch in and the engine actually isn't even at idle, so it's nothing to do with the throttle.

So annoying.
____________________
Current: Yamaha FZ1 '07 | GSXR 750 SRAD

Past: CB125TDC | TZR125 | GPZ500 | CBR600F3 | ZX9-R | GSXR1000 K4

[P.]

Hence ignition.

Possibly time to whack those fairings off and have a look round the loom. Ignition down to the coils, on to the HT leads.

[Snorty]

This is way beyond me at this point I think.

I don't have a multi-meter, I don't have many tools, I think I'm going to have to take it to the garage. Perhaps I've saved myself some money in diagnosing it.

Have to wait a couple weeks now and ride as-is, til I can afford it.

The throttle position sensor is quite low I think? It says _c00, though I doubt this will be the problem, I may as well get it fixed at the same time.
____________________
Current: Yamaha FZ1 '07 | GSXR 750 SRAD

Past: CB125TDC | TZR125 | GPZ500 | CBR600F3 | ZX9-R | GSXR1000 K4

[Kris]

Does it have an alarm / immobiliser?
____________________
NSR125RR - ZXR750H1 - ZX9R E1 - GSF600S - GSF600SK3 - VFR400-NC30 - SV1000N - ST1100-R - CBR900RR-R - GSF1200SK5 - GSF600SK1 - VFR1200FA - GSXR1000K2 - ZZR1400 D8F
www.prisonplanet.com

[Fisty]

Its a coil.
____________________
Quietly and consistently taking the piss.
TL1000R | Hayabusa | ZXR400 | TL1000S | Bandit 400 V
Fatter and faster than Fret

[sickpup]

[Fisty]

[Snorty]

I reckon it's a connection fault as you say - I took it quite far today without any of the symptoms, revved it up to 12k rpm up the road with no ill-effects, then it started randomly doing it again.

Seems like if the coils were gone, they'd not be intermittent? Whereas a wiring fault is? I'm probably wrong though.

I will add at this point - the battery had been run completely flat by a knackered rectifier - to the point where it was absolutely drained. New rectifier was fitted and the battery charged itself back up. Don't suppose this could have any bearing on the situation?

Also, I meant to ask, you guys know what you're talking about - what effect does the throttle position sensor have, in real terms of riding the bike? As I say mine is at the bottom position
____________________
Current: Yamaha FZ1 '07 | GSXR 750 SRAD

Past: CB125TDC | TZR125 | GPZ500 | CBR600F3 | ZX9-R | GSXR1000 K4

[P.]

[stonesie]

WOAH FELLAS!

Try the wiring and connectors first, then move onto the spark plugs, they can also break down and start to misfire under load when the temperature rises rapidly then go back to normal service when they cool.

Cheapest fix first

My bike was running not bad maybe slightly lumpy but nothing really to worry about, 8K miles from new and the plugs looked like this...

https://img821.imageshack.us/img821/6214/imag0126f.jpg

[Pete.]

Duff plug won't throw an FI light - the ECU has no way of knowing about it.

Stick coils have a habit of cracking and breaking down. Swap the two coils with the other two and see if the fault moves.
____________________
a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good

[Snorty]

Just been out on the bike now, did around... 6 miles. The last two miles I caned it where possible... no fault code, no problems.

I don't know if this helps narrow things down for the more knowledgeable?
____________________
Current: Yamaha FZ1 '07 | GSXR 750 SRAD

Past: CB125TDC | TZR125 | GPZ500 | CBR600F3 | ZX9-R | GSXR1000 K4

[stonesie]

I hate electrical faults

First thing to do is check all the wiring connectors that have anything to do with the coils, a shot of WD-40 or ACF 50 won't do any harm. Any green fur in there or rust is corrosion and needs cleaning out if possible.