2008 Nytro bogging and hestitating but very random. Need advice

[MattG]

Hi all,

I have a 2008 Nytro RTX with 8,500 km. It starts well and generally runs well, however, on every ride at some point the engine will bog and hesitate so the machine becomes very jerky, mostly at lower speeds (like the engine is cutting in and out). When it does this, it will often stall if I come to a complete stop and do not give it any throttle. It will start right back up however. At times I have have ridden for over an 1.5 hours and nothing and then other times it happens sooner. If i give it a bunch of rapid throttle bursts it often goes away or if I turn the machine off it sometimes resets it. It is strange because when doing it, I can give lots of throttle and it responds, so doesn't seem like the injectors. On a recent 3 hour ride it probably did this 3 or 4 times but most of the ride is fine., My first suspicion was the TORs, however, I am pretty sure this has been deleted and it is still doing it. Looking for some help as I feel like it may not be a cheap diagnostic at the dealer. It is rideable but super annoying and concerning. I have scanned many threads and other than TORs not seen anything similar, other than fuel filter suggestions or water in the fuel. I feel like there are so many electrical things it could be (like related to the CDI or fuel injectors). Any help would be appreciated. Thanks Matt

 

[MrSled]

It only happens on deceleration? or at idle like when coming to stop signs? How many miles on it?

 

[MattG]

8500 km. I notice at lower speeds, generally when slowing down, when I let off the throttle and then then go to apply the throttle again. Then it bogs and hestitates. If you are standing up, it is quite jerky. Only does it once in a while but on every ride.

 

[MrSled]

8500 km. I notice at lower speeds, generally when slowing down, when I let off the throttle and then then go to apply the throttle again. Then it bogs and hestitates. If you are standing up, it is quite jerky. Only does it once in a while but on every ride.

if it stalls it could need a valve adjustment but it sounds like it needs fuel..

 

[MattG]

If I give a little bit of throttle it does the jerky bogging thing. If I really squeeze the throttle is fires right up. So maybe it is periodically being starved of fuel... Thoughts on reason - fuel pump?

 

[Mooseman]

Check the main ground wire from the battery. It has a spade connector that can corrode or become loose and cause weird occasional electrical gremlins. Had that happen on two sleds. Just cut out the spade and solder wires together. No need for a connector there.

 

[maim]

could be a worn spot in the throttle position sensor as well.

 

[MattG]

Thanks guys, I will look at the ground connection today or tomorrow and report back. Regarding the throttle position sensor, if that were the case, I would have to replace correct?

 

[74Nitro]

It sounds to me like the TORS is kicking in. Something is out of adjustment. Do you have a handlebar riser?

 

[MattG]

That was my first thought when it started happening and reading other threads. I followed some instructions to delete and I think it worked as I can check by reving it on a stand I.e. manipulating the throttle control switch before i squeeze and it does not cut out etc. Will verify though.

 

[MattG]

Handle bars are regular. I did remove a bit of slack.

 

[74Nitro]

I didn't know these could be deleted. Make sure you have proper freeplay and that it doesn't change when you turn all the way to the left and right.
I also noticed that the TPS sensor does supercede to a new part number. That is sometimes an indication of a faulty part.

 

[MattG]

Ok thanks! Will report back after more trouble shooting.

 

[74Nitro]

You can use diagnostics to check and watch the operation of your existing TPS

 

[MattG]

Ok thanks will have to look up that one. I have seen some videos on how to do such things.