Polaris Dragon 2009 800 w/ turbo died, starts breifly, backfires

[kroude]

Was out riding for 2 days. 3rd day, we rode for about 15 minutes. All the sudden, the machine just died.
It is a 2009 Polaris Dragon 800 with a boondocker fuel controller and turbo.
Had it about 5 years and when I first got it, it would cut out after getting warm. Figured out it was the ECM and replaced it.
First 2 days it rode great. Then it died as I turned around to head back to help someone that was stuck.
When I pull on the cord, it won't start most of the time. Then, it will for a few seconds.
Feathering the throttle doesn't help. It won't rev up and acts like it is bogging when you give it throttle.
If you let it idle it just dies after a few seconds.
Sometimes it backfires. I've now broken the pull cord on one of the back fires. (Think some rope is sticking out as I had just replaced it and left some extra so fixing that won't be difficult.)
Here are the things that changed from day 2 to day 3.
We noticed the clear cap on the gas cap had fallen off. So, there could be water in the fuel.
I just added Stabal to it before trying again and breaking the pull cord (which led me to look for help.)
We added about a gallon of high octane fuel. Ration is supposed to be 1-5. There were about 8 gallons in the tank and already had some high octane fuel. Maybe too much?
Elevation was the same each day and now I'm down at 400' and still doing the same thing.
Other thing I noticed was it seemed like the throttle cable was stretching a little. While trying to get it started, the end of the cable actually came out of the throttle body and had to put it back in. Don't know if it was way worse than before but did seem like there was more slack in the cable. I did have a new steering column put in it before the season but don't think that affected anything.
Thankfully we hadn't gone too far in the 15 min and the tow back to the trailer wasn't too hard.
I"m just at a loss of what it could be. I don't even know where to start trouble shooting.
Could the water in the gas actually make it backfire? How could the timing get off like that?
It is definitely getting spark. Seems to be getting some fuel. Could be the fuel filter but not sure why that would make it backfire. ??
Same with fuel pump. I could see where some gas would eventually feed in enough to get it to start but then not let it run but why would it backfire.
I tried to search the forums for a similar situation but either not there or I don't know the right terms to use.
Open to suggestions. Thanks in advance.

 

[KBP]

Did you check compression? Those motors are known for this issue, and it needs a top end rebuild.

 

[chvypickupman355]

IF you have decent compression and it is within 10% difference between cylinders, I would unplug the boondocker controller and plug everything back in as stock and see if it will idle and run normal. If it does then you have an issue with fuel controller. You can turn the boost way down if you have an adjustable wastegate actuator and you could probably finish off your trip riding it.

Next electrical problem I have had is the voltage regulator can fail and cause this same issue.

If you think you have water in the tank you could get a syphon pump and suck off the bottom of the tank. Put the gas in a clear jug and see if there is water at the bottom.

Good luck.

 

[kroude]

Think it has to do with the timing sensor on the stator plates. Checking into that. Actually talked to the Arctic Cat Repair shop in my town on some other stuff and mentioned this problem. That's what he though it was and his description sounds correct. I've checked a bunch of other stuff and none of it seemed to be the problem.