Fired up my Busa (’02) for the first time after winter mods and sorting a problem with the starter. Engine has been bored out to 1396 and was running 100% before the winter.
Seems to start ok and idles a little roughly but not too bad, has v.good oil pressure, however when it's warmed up I try to rev it and gets to around 6K and then starts miss firing, stuttering and won't rev any higher.
Winter mods consisted of upgrading fuel system with braided lines, Aeroquip fittings, Aeromotive regulator and Sytec pump. All of this appears to be working well with fuel pressure remaining constant. Have also checked all the filters etc and the seem fine (ie no blockages). Everything seems to be plumped up the right way. Everything else on the engine is as it was before the winter. Only other thing I did to the engine was take the clutch out to inspect it and put it back in again.
All made zero difference.
Hooked up my a lambda gauge which sits nicely around 0.95 when idling, then suddenly goes crazy around 6k with the mix appearing to lean right off relatively suddenly.
Struggling to think of anything else apart from the injectors being fouled. Injectors are currently being ultrasonically cleaned by local tuning company, so will see what difference that will make.
Not running with the standard Busa clocks, so trying to get my hands on a set of these so I can check for any error codes.
Also planning on working my way round the various sensors (CKP, CPS etc) and check these as per the Suzuki maintenance manual.
Any thoughts or suggestions on what else to try will be much appreciated.
Seems to start ok and idles a little roughly but not too bad, has v.good oil pressure, however when it's warmed up I try to rev it and gets to around 6K and then starts miss firing, stuttering and won't rev any higher.
Winter mods consisted of upgrading fuel system with braided lines, Aeroquip fittings, Aeromotive regulator and Sytec pump. All of this appears to be working well with fuel pressure remaining constant. Have also checked all the filters etc and the seem fine (ie no blockages). Everything seems to be plumped up the right way. Everything else on the engine is as it was before the winter. Only other thing I did to the engine was take the clutch out to inspect it and put it back in again.
- I tried re-fitting the old fuel pump, which made no difference.
- Also added new plugs, and then tried refitting the old ones, again no difference.
- All coils seem to be fine have tried replacing all with a spare that I have.
- Have put a temp gun on all the exhaust headers when running and these are pretty much equal.
- Battery has plenty of charge and voltage when running seems to be good.
- Checked all my fuel lines and no kinks or bends or restrictions.
- Double checked all TB vacuum lines all of these as normal.
- CAT/Exhaust etc all in good nick.
- Tried with full tank of fuel.
- Never really messed with any of the wiring on the engine since the engine was last run, but everything looks as it should be.
- Double checked set up of the new regulator, which seems good (set to 55psi which is what I had before and what was recommended to me by my engine builder/tuner. Tried varying the pressure but again this made no difference.
All made zero difference.
Hooked up my a lambda gauge which sits nicely around 0.95 when idling, then suddenly goes crazy around 6k with the mix appearing to lean right off relatively suddenly.
Struggling to think of anything else apart from the injectors being fouled. Injectors are currently being ultrasonically cleaned by local tuning company, so will see what difference that will make.
Not running with the standard Busa clocks, so trying to get my hands on a set of these so I can check for any error codes.
Also planning on working my way round the various sensors (CKP, CPS etc) and check these as per the Suzuki maintenance manual.
Any thoughts or suggestions on what else to try will be much appreciated.
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