Hello everyone
My 2015 Polaris runs horrible when cold. Misses, stalls, sputters, boggs down. Once engine is hot or warmed up to the point the cooling fan is kicking on it runs great. Less than 50 miles on it and less than 25 hours.. Although it may be a coincidence, it started to run rough after its first service. Ran great before that. Took it back and they replaced plug, cleaned or replaced injector, reset factory computer settings. It ran great when I picked it up but of course it was totally warmed up.. Please help..

Thanks

 

Take it back it's still under warranty or even if it isn't.Let them find the problem.Could be a sensor or wiring harness problem that they can check out on Digital Wrench.Only so much you can do in the garage with a multi meter.

 

Is there any chance that there is moisture in fuel tank causing the problem. I have tried moisture removal additives. No help. I suppose if there was, it would run rough all the time not just when cold?

 

If it runs good when warm shouldn't be the fuel. I'd still take it to the dealer that worked on it and let them find the problem.

 

So I took my ETX back and now they are checking the timing, cam, etc. They changed the fuel, tested numerous other things, and Polaris said next thing to check would be the timing. I guess that requires a partial tear down? I called them and told them I thought they were missing something much more basic than tearing engine apart.. I am getting very frustrated. Any thoughts appreciated. As far as I kmow, sensors have been checked but there has not been a thorough harness check. I suggested they look at the obvious. ..

 

Even Digital Wrench can miss harness problems. May or may not be your problem,but harness repair kits kept us busy on efi models. Popping back,stalling,no or erratic idle was usually related to the tbap harness or connector,not the sensor itself. Don't know if this place that has better repair kits has ones for these later models.Polaris techs would use the same thin wiring and connector kits.https://otbpowersports.com/products/

 

Thanks for the input. I will post an update as soon as they call me with the results from checking timing parts. Hopefully today. Just so I understand, there are numerous harnesses? Finding which one might be bad is the trick?

 

Usually the tbap,sometimes the tps harness if it's a wiring or connector problem. On the older machines you could sometimes wiggle the harness and notice a change in the way it runs. Unless Polaris has updated these thin harness wires(about as thin as telephone wires) wires can rub bare spots,short to ground, or can melt internally. Soft feeling wires are an indication of this. Hopefully the dealer can find the problem whatever it is.