Issues with 08 nytro. Thoughts and Opinions please!

[Throndson]

Hello everyone.
Seeking some advice/opinions on some strange issues that have came up on my 08 nytro mtx.
I bought this machine new at the end of 08 and have had virtually no problems up until several weeks ago.
Sled is basically stock (different handlebars and 09 subframe) with under 3000km (1800miles).
Recently got error code 84 (TORS throttle overide sensor). I inspected my throttle cable down to the throttle body and did not find anything wrong. I recently put a new bar and riser on and was hoping that was why the TORS was acting up. It only acted up with a rough idle after sled was warm and I was idling. I remedied this by disconnecting the TORS as learned on snowest.
Next day of riding the error code and annoying orange blinking light was gone. Problem solved I had hoped.
I then noticed an odd popping or like a drum like sound that sounds like its coming from my exhaust particularly around 5000-6000rpm. Its less noticeable when on the gas above 6000. Its usually 3-4 "thum thum thum" almost like its missing although the engine doesn't seem to hesitate.
Its not affecting the performance as far as I can tell but Im sure the noise wasn't there before.
I thought it might be water in the fuel system and used a "seafoam" product to try and remedy. The noise is still there.
I also discovered that when the machine is idling and I tip it over at about a 45' angle to the left the idle drops significantly and runs very rough. doesn't affect it when tipping to the right???
I appreciate any comments or opinions on the potential problem.
Thanks in advance!

 

[constech]

08 Nytro

When you disconnect the TORS system you should install a kill tether to shut down the motor in case of stuck throttle. I have disconnect on all of my recreation vehicles as they are definatly problematic. The small miss sounds like it is fuel related where it changes from leaning it side to side and only in mid throttle I would suspect accelerator pump. Not sure how to check it however.

 

[bholmlate]

Throndson
That TORS system is really sensitive. I am sure it had to do with you replacing the bars and moving the throttle houseing on the the new bars. I had a left handed throttle on mine for awhile and it played havic with the TORS system. I finally removed the left handed throttle and things went back to normal.
If you tip the sled over on the left The rough idle could be caused by oil running up the breather line and being dumped into your air box and run through the motor. Oil does nasty things to the sparks plugs since it burns a lot hotter then fuel.
If the sled is tipped to the right the oil is less likely to run up into the air box. There is still pressure pushing it up from the oil rushing back into the tank from the bottom of the motor but it is still less likely to make it all the way into the box if the sled is tipped over on the ride side verses the left side. Not sure what the other issue might be caused by. Might be time to change out the spark plugs if you havent already to see if that fixes the issue.
I know if you run an aftermarket exhaust sometimes under hard acceleration the motor will sound like it is missing. but that is only under hard acceleration. It was explained to me as an issue with the engine breaking circuit in the fuel injection system. the circuit opens causing a slight lean condition under certain conditions while accelerated. I have heard the same thing can happens with the stock setup but it is quieter and less noticable with the stock setup. Hope you figure it out.

 

[Throndson]

Im going to try new plugs hopefully tommorow.
Anyone have any recommendations on replacement plugs?

 

[TRUEBLUEMAX]

I went with the same as stock heat range plug but in the iridium plug. I like iridium plugs a lot.

 

[BigFish BC]

your torrs issue was from the new bars & riser, was putting too much tension on the throttle cable. you just needed to adjust your throttle so when you push it, it has a little bit of play before the cable starts to move.if there is no freeplay the torrs will kick in because it thinks the cable is froze.

 

[chem]

I also have an 08 Nytro MTX which was behaving similar to yours. It turned out that one of the wires from the throttle position sensor had rubbed against the frame and rubbed away the insulation. There would be an occasional short of the TPS signal, and my sled ran very poorly. The "popping" or "drum" sound you spoke of sure seems to be similar to what I was hearing.

In my case, I put the sled into the diagnostic mode to monitor the TPS. By wiggling the wires coming from the TPS, I was able to find the short (about 6 inches from the TPS where the TPS wires joined a large bundle of wires next to the frame)

 

[Throndson]

Thanks Chem!
Nice to hear someone else has heard the drum. Been thinking it was in my head but I am certain its not.
Been having some irregular idling action also when the idel drops below 1000 and its struggles to stay running.

 

[Throndson]

I made sure my cable was adjusted within spec. the TORS was still a problem.
I also replaced my plugs with iridium plugs and the popping/drumming has yet to be gone.
One of my plugs was corroded on the top (not the part in the cylinder). Must of had some moisture get into the coil. Im going to try a multimeter on the coil and make sure its working right.
Next ill try Chems suggestion also once I learn more about the diagnostics etc. If that doesn't work I suppose its off to the dealer. Im afraid of what that is going to cost. Hopefully I figure it out before it comes to that.

 

[bholmlate]

It looks like you are at least on the right track to solving your issue. If you do end up solving it please post what you founf out. that would be a great help to the rest of us that may run into this issue at one point.

If your TORS is still acting up and everything is within spec at the handlebards then the signal from the TPS could be erratic. Also not sure you have seen the other post right below this one about the engine running rough. Here is a link http://www.snowestonline.com/forum/showthread.php?t=299878

If you have not already looked at it there might be some information your could use as well. I think it was started by CLEM who has already comment in this post as well

 

[big_red1a]

How many miles? Have you considered exhaust donuts making the sound? Is it like a backfire sound ?