2018 Mtn Cat Problems

[Toyotajoe]

Hey guys, 2018 Mtn Cat 800 CTec2 with approximately 600 miles...

Had a great week on the sled however as returning to the truck on the trail a few days ago, I noticed the sled would not pull RPM’s above 7600. When you pin the throttle, Rpm’s would jump to 7600 and the sled would REV no further, but sounds like it hits a rev limiter (for those of you familiar with sport bike rev limiters - sounds just like that).

Dropped the sled off to my dealer for a couple of days and they couldn’t find anything that really stood out. They adjusted the APV’s, replaced what appeared to be a bad APV cable, and I took the sled back. They also checked both clutches and springs, everything checked out OK.

Yesterday a few of us headed into the backcountry. From where we park our trucks, we ride across a lake for a few miles to get to the hills on the other side. The sled initially ran great, RPM’s were hitting 8100-8200. After a few miles on the lake however, the problem reoccurred and the sled began hitting the “rev limiter” and topping out at 7500. This persisted throughout the day, with the sled hitting the “limiter” at different RPM’s throughout the day. Sometimes 6500, 7000, 5500, really inconsistent and all over the place.

I did notice that every time I parked the sled for 20 mins or so, the problem would go away and the sled would run great again for a short time, eventually returning to the “rev limiter” state of mind again. It did not seem related to coolant temperture as the sled exihibted this problem at all temps between 105 and 140*F.

I dropped the sled off at the dealer again today in hopes that AC will give them some guidance and they can pursue the problem further. If anyone could offer some advice, I would appreciate it.

[kiliki]

Bad roller in the primary or tss.

[Old & slow]

Originally Posted by Toyotajoe

Hey guys, 2018 Mtn Cat 800 CTec2 with approximately 600 miles...

Had a great week on the sled however as returning to the truck on the trail a few days ago, I noticed the sled would not pull RPM’s above 7600. When you pin the throttle, Rpm’s would jump to 7600 and the sled would REV no further, but sounds like it hits a rev limiter (for those of you familiar with sport bike rev limiters - sounds just like that).

Dropped the sled off to my dealer for a couple of days and they couldn’t find anything that really stood out. They adjusted the APV’s, replaced what appeared to be a bad APV cable, and I took the sled back. They also checked both clutches and springs, everything checked out OK.

Yesterday a few of us headed into the backcountry. From where we park our trucks, we ride across a lake for a few miles to get to the hills on the other side. The sled initially ran great, RPM’s were hitting 8100-8200. After a few miles on the lake however, the problem reoccurred and the sled began hitting the “rev limiter” and topping out at 7500. This persisted throughout the day, with the sled hitting the “limiter” at different RPM’s throughout the day. Sometimes 6500, 7000, 5500, really inconsistent and all over the place.

I did notice that every time I parked the sled for 20 mins or so, the problem would go away and the sled would run great again for a short time, eventually returning to the “rev limiter” state of mind again. It did not seem related to coolant temperture as the sled exihibted this problem at all temps between 105 and 140*F.

I dropped the sled off at the dealer again today in hopes that AC will give them some guidance and they can pursue the problem further. If anyone could offer some advice, I would appreciate it.

Mechanical problems in most cases work or don't work. Electrical on the other hand can be intermittent. There has been a few fuel injectors failing. Check harness at the injectors some have rubbed through. As temp rises under the hood everything expands slightly and may be enough to cause the wire to ground out, that explains why the sled runs good after a 20 minute break. More things to check, vent/ check valve for the fuel tank, drain the fuel and try fresh,check all electrical connectors and put dielectric grease on them. Barometric pressure hose on ecm must be open.

[madmax]

Kinda sounds to me like you were over heating.

[Toyotajoe]

Originally Posted by madmax

Kinda sounds to me like you were over heating.

Nope. Endless powder throughout the day and temps in the 105-120 *F range for the most of the day according to the gauge.

[tinkerjohnson]

How about pipe temp sensor? I herd of problems with them.

[Toyotajoe]

Originally Posted by tinkerjohnson

How about pipe temp sensor? I herd of problems with them.

That could be, you would think the sled would throw a code if it were sensor related but weirder things have happened I guess.

Hopefully the dealer figures it out.

[rkm]

I had a pipe temp sensor fail but no code. The guage will show the exhaust temp reading to aid in diagnosis.

[Ktmsx350f]

No CEL ? Pipe sensors on these have gave a few guys issues from what I have red. Does it do the same thing if your role into the throttle or have it not quite wide open day 90% throttle ? Fuel pump and or filter will do this and not set a code because frp isn’t monitored and it’s a open loop system.

[Toyotajoe]

Originally Posted by Ktmsx350f

No CEL ? Pipe sensors on these have gave a few guys issues from what I have red. Does it do the same thing if your role into the throttle or have it not quite wide open day 90% throttle ? Fuel pump and or filter will do this and not set a code because frp isn’t monitored and it’s a open loop system.

The problem isn’t as prominent if you roll onto the throttle but is still there. The dealer has replaced the engine temp sensor believing it may be faulty, putting the sled into sort of a limp mode. All my snow is gone for the season so I’ll guess I’ll just have to,wait until next season to see if the problem was solved.