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Stalling at low idle.

spoon

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Just started yesterday. 2014 800 non ES stock with PCV and porting. When letting off throttle at near stop sled will idle low and not rev up, bogs when applying throttle. Feather throttle and might rev up or shut off and restart it is good to go for a bit. Air/fuel guage reads full lean when happening like fuel pump isnt keeping up. Shut it off and as long as revs are past 4000 no issue. Let off to go through a trough or around a tree it falls on face and needs reset. Sure it is electrical as it is intermittent but getting worse throughout day. Went to go to truck to get spare sled and acted up on startup but never missed a beat all way back to parking lot. Downhill 20 minutes very little load. Thinking stator or voltage regulator. Couldnt get guage in volt mode when happening without stalling first. Running a headlight delete. Could this damage stator? I know M7s had issue with this. Didnt think Proclimb wiring had same issue. I have other good stators/regulators to try but cannot duplicate at home. Voltage reading 14-16 at idle. My 2016 reads 12-13 at idle but has headlights. Anyone else experience this? My voltage too high and causing stator failure?
 

boondocker97

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Something simple, but check your primary spring really well. I had a spring break in my prolite right near one end. If I could get it to rev up it would run fine and wasn't super off on top end RPM. Would bog and try to kill the sled at takeoff.

The stators are supposed to be able to run without the headlights, but mine has eaten two of them. first one at 2400 miles or so (?) and second used one after 2700 miles. Headlight delete since new and it did kill a voltage regulator before the 2000 mile mark. Shannon at the Cat shop in Cooke City told me all the ones he changed stators on had headlight deletes. The fuel pump circuit has it's own winding though so IDK.

Found a spot on wire harness behind chain case that wore through and touching intermittently too.
 

IDspud

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That’s what I had in mind, my primary has killed my motor like that before. Rode out once after pulling with a dalley to ten mph, pull rope, starts and drop dalley, ran great until slowing under 5, kill engine, repeat.
Broken Clutch wouldn’t release belt completely, stalled motor at slow.
 
K
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Bog at low rpm, comes out of it sometimes, inconsistent throttle response? I would start with the TSS, possibly loose throttle cable keeping the TSS from working as intended.

Broken primary spring will cause your sled to "creep" when at idle.

Have you ever adjusted your throttle cable since owning it?
 

Old & slow

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Just started yesterday. 2014 800 non ES stock with PCV and porting. When letting off throttle at near stop sled will idle low and not rev up, bogs when applying throttle. Feather throttle and might rev up or shut off and restart it is good to go for a bit. Air/fuel guage reads full lean when happening like fuel pump isnt keeping up. Shut it off and as long as revs are past 4000 no issue. Let off to go through a trough or around a tree it falls on face and needs reset. Sure it is electrical as it is intermittent but getting worse throughout day. Went to go to truck to get spare sled and acted up on startup but never missed a beat all way back to parking lot. Downhill 20 minutes very little load. Thinking stator or voltage regulator. Couldnt get guage in volt mode when happening without stalling first. Running a headlight delete. Could this damage stator? I know M7s had issue with this. Didnt think Proclimb wiring had same issue. I have other good stators/regulators to try but cannot duplicate at home. Voltage reading 14-16 at idle. My 2016 reads 12-13 at idle but has headlights. Anyone else experience this? My voltage too high and causing stator failure?
I can't remember if that year has a idle speed motor or not. If it does not then I would check the air intake sensor for proper ohm's. I think someone made a relocate kit for the air sensor possibly speed werx not sure, but the kit was for your same problem if I remember right. The relocate moved the sensor from up in the hood to down on the intake. Another thing to check is the tube coming from the ecm make sure it is clear and not kinked.
 

spoon

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Temp sensor relocated to airbox already, MAP tube from ECM is clear. Seems voltage/fuel related as low rpm equals lean air/fuel and as soon as you can coax it up to 3000 or stop and restart it is good again for a bit. Needs load and use to duplicate. Low load to get down mountain to truck and running it at home I cannot duplicate concern other than voltage being higher than I think it should. Going to try a voltage regulator first and maybe add a headlight or resistor for more load on system.
 

Old & slow

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Could it be a sticky exhaust valve or the PCV? Just spit balling ideas. It will be interesting to hear if the voltage regulator clears it up.
 

High Life

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Spoon, did you ever resolve the issue with your sled? I'm having a similar problem with mine. 2017 Mtn Cat 925, headlight delete, PCV. Always starts, but sometimes has a low idle and as soon as I touch the throttle it drops the r's even lower eventually killing it. Have had it quit on me when descending hills at idle. Tried adding and pulling fuel on the bottom with the PCV, but no luck. If I can re-start it and quickly blip the throttle to get the R's above 3000, I'm good to go. It does run inconsistent on the upper R's, but I have attributed that to simply being out of tune with my PCV...

Primary spring was nearly new and I have since replaced it with a different spring and it does the same thing with both. Put a fuel pressure guage on it and it reads about 45 psi. It is not a liquid filled guage, so the needle shakes like crazy around 45 psi so I'm guessing my fuel pressure is OK. Actually got the sled to act up in the shop after I put the fuel pressure guage on, and while the R's dropped, the fuel pressure held steady. Seems like if I let the sled idle long enough, it will eventually act up.

On my old M7 big bored to an 800, I burned it down due to an injector getting completely plugged. Took the injectors to an automotive shop and they flushed/cleaned them and said they had a hard time getting the one cleared.

I'm thinking I need to be looking at my voltage regulator, stator, etc. Guess an inline fuel filter wouldn't be a bad idea either since I could have an injector partially plugged or dirty.
 

spoon

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Haven't ridden it since issue occurred and cannot duplicate at home. Took my other sleds out as I didn't want to ruin a ride. Added a spare voltage regulator to pack for when I do. If not that then will unplug and bypass PCV. I can ride sled without for trail riding. I do have a spare PCV I may throw my same program into and carry it as well. If either of those don't fix I will try a stator. I have all these parts anyway but hate having to guess when out riding.
 

High Life

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I just figured out how to display voltage on my factory deluxe gauge. I'm showing 14.2 to 14.9 volts at idle. This is with a headlight delete and small LED headlight.
 

spoon

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Follow-up as no one usually does. Checked all connections and swapped out PCV with another and took it on a good ride and only had issue once on a cold startup which I have had happen on other sleds randomly and usually ignore. Shut off and restart and ok. Not positive about PCV but took sled to Revy last weekend and it never missed a beat. Never said it on first post but this is my 1000 swapped 2018. I knew engine had nothing to do with it and all electronics minus knock sensor are same as 12-17 Proclimb. The PCV I was using is one for boost and I was just letting the boost sensor hang in atmosphere. Replacement PCV is for normal setup and was planning to swap out anyway so I could use the boost one on something else. Appreciate all the input and gives me more ideas for troubleshooting in future.
 
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