Need help

[blew by you]

My nytro is sputtering and crackling bad when i really get her nice and hot especially when i stab it...i know i dont have a fuel tuner but i've been running without one for 3 years...changed plugs,fresh fuel,seafoam still no difference...load tested battery,its fine...i'm pretty sure my donuts are leaking or gone all together...would that be the cause? is there a fuel filter on this thing? tried a search couldn't find anything...ANY INFO WOULD BE APPRECIATED!!!

 

[JP270NYTRO]

if your they are gone you would notice the sled being alot louder and when you let off it should pop almost like a backfire as for sputtering usually plugs are the cause of that...

 

[blew by you]

its definetly louder and has that pop but i just put in new cr10ek plugs in it...could it be a plug wire?

 

[natedawgedog]

if your donuts are gone you will get symptoms as you discribed, happend to me, 2 of my donuts were about gone... unless you like hot exhaust gases 6-8 inches away from your gas tank, I would at least inspect your donuts to see if they are bad.

if it was a faulty plug wire or coil your machine would sound like it was running ruff or on less cylinders than normal, it would also throw a code.

 

[blew by you]

i checked the donuts...they're good.Noticed my air box was popped off of the throttle bodies (due to a 1"thick branch that pushed its way through a side panel and wedged its self between the airbox and the block) clamped that back down still running like its on 2 cylinders...no codes...only does it when it warms right up...also bypassed tors...how do i check for a faulty coil? any other ideas? I REALLY NEED TO GET THIS FIXED GOING TO TOGWOTEE IN 2 WEEKS! I'M TOTALLY STUMPED!!!

 

[mx1500]

check ur throttle cable, make sure plug caps are on good, no pinched fuel lines? relays

 

[blew by you]

i have it at the dealer right now(who i don't have a lot of confidence in) they are stumped...they checked fuel pressure 48psi seems fine but they checked it without it running does that make a difference? tps checked fine...coil resistance is fine but i recomended a spark test on heat soaked coils...I'M DESPERATE GUYS...RUNNING OUT OF TIME...anybody have any thoughts???

 

[blew by you]

The dealer has had it for 3 days now...they are no further ahead and they have not called yamaha canada for technical support... i'm extremely frustrated with them...DON'T KNOW WHAT TO DO

 

[Len Todd]

If you bypassed TORS correctly, we can rule that out. Also, that would give you a code.

I think you can remove the grommets and re-install the coils and look for the arcs in a darkened room. If the coils' resistance checks are O.K. when hot and they are not arcing, then they are not the problem.

I assume the sparkplugs are clean and have not been miss-handled.

Check the coil wiring coming out of the engine for chaffing or breakage. If I recall correctly there was some problems the wires chaffing and or breaking. Resistance Test the coil when hot. You may have to disassemble the engine to visually inspect its internal coil wiring. I had a sled coil that when it got hot the thing would change resistance and the engine would run badly and then quit. When it got cold it would run again. Eventually it failed open.

Check all other wires for chaffing. Start at the ECU and work you way back to the sparkplugs.

Have you tested the injectors? Have you cleaned all connections? Back of Gage, ECU, injectors, coils, Fuse connections, etc.

 

[blew by you]

My fuel pressure goes down to approximately 40 psi. when I get that stuttering spec is 46psi...does anyone know if that is a significant enough drop to cause this condition

 

[Len Todd]

6 PSIG below spec would lean you down about 10 - 12%. That could cause significant problems. But performance wise, it would be just running lean versus sputtering. Typically sputtering is an electrical problem.

I can not remember if there is a separate pressure regulator or not. It could be that fuel pressure regulation is just part of the pump. The fuel system pressure needs to be brought back into spec even if it dos not fix the problem. If you are lucky, it may even fix the problem.

 

[blew by you]

an update on my POS:
Swapped out the fuel pump,entire intake,thermostat along with coolant temperature sensor and battery and coil...sled is running worse than ever misfiring and back firing badly...it was at the dealer for a week they can't figure it out niether can the yamaha techs they suggested running it with a voltmeter on the battery 13.9-14.2 volts which i believe is normal...I'M LOST...love this sled but its cost me $900 in rental in Togwotee,replacement of certain parts and i haven't received a bill yet from my dealer LOOKING FOR ANSWERS!!! if i can't fix this thing i hate to say it but i'll be jumping ship...if YAMAHA themselves can't figure this out how can i justify staying with them

 

[poor farmer/logger]

Have you or your dealer checked the wiring for bare spots or corroded connections? My guess is you've got 1 or 3 things going on. Something shorting out somewhere, a corroded connection or a poor connection in the wiring. If you or they haven't gone threw the wiring I think that's the frst place I'd start.

I had some problems with a wiring harness on the left hand side in behind the secondary clutch on the rad mount. Mine would blow fuses though. Still maybe worth a look though just to make sure.

Ryan

 

[nauti1]

Did they perform a compression test or a leak down test? It sounds like your lean condition may have burned a valve. Oh I would look for another dealer, sounds like they don't have mechanics, just parts changers.

 

[blew by you]

apparently they performed a compression test and it checked out...with the voltmeter reading 14v on the battery with the sled running does that rule out a stator and rectifier problem/issue?