problem with Polaris Sportsman 110 EFI
 

Hi All,

Santa brought a new 2018 Sportsman 110 EFI to my son last Christmas. All was excellent until earlier this week while we were doing our normal scooting around our East Texas property. After riding for about 10 minutes that night, stopping briefly (with engine still running), suddenly his quad just wouldn't move. Engine light came on. Engine sounded like a purring cat as usual - no problem...but the quad wouldn't move in forward or reverse. It tries.... but when throttled the engine seems like it's limiting revs ...and the RPM's are not getting to the level of actually getting the thing moving past a slight nudge...then it goes back to idle. If throttle is continuously held, it will keep trying to move, then throttling back, then trying, etc.... very quickly.

Towed it back to base, checked the obvious things. Oil level fine, spark plug wire secured, battery cables fine, O2 sensor (I assume) wires look fine, various electrical connectors look fine with no (obvious) signs of wire chafing anywhere.

Any ideas? Of course we're just out of the 6 month warranty.... right now it's back in our garage in Dallas, sick to its (and my) stomach.

Thanks,

Bill

If a video of this behavior would be useful (to post to youtube or to send via cell phone, whatever), I have one from today.

Have you checked the cvt belt, it may have gone bad or come apart.

I haven't yet. I was hoping it wouldn't be that, as I've heard horror stories on replacement cost.

I unplugged the front relay as well as another loom. Plugged them back together and now I can't get her to start at all.......

I believe I found the reason for no start.... somehow (no idea) the sensor (p/n 0455053) broke at the brass/plastic interface. This sensor threads into the bottom front of the engine on the left side where a 2-wire harness plugs into it. The harness side connector was also broken. Wires were just hanging there. This sensor description, according to online research, is a coolant sensor. However, this quad is obviously air-cooled...so I'm not sure what the function of this could be. Maybe temp. At any rate, it appears it's about a $140 part. Wondering if there's an alternative automotive p/n with same specs that could be used. I can't say if this is also related to the no-move situation in my original post...but kinda hoping that the sensor was in the process of failing/breaking causing the entire issue.

"it's about a $140 part."

The joys of EFI.Can't see any reason to make kids Quads EFI (or any other quad for that matter). Just spent £180 on a new ECU (computer) for an old model Honda 420, plus an afternoon of tracing wires to find why it blew fuses and soldering rodent damaged wires in the battery box. Fitted a new £30 Chinese carb to a Honda 350 the next day. Both run fine now.

The sensor will be a standard auto part, but your chances of finding the right one are slim. Belts shouldn't be expensive, genuine ones possibly, but almost certain to be Gates aftermarket belts available for circa $30.

"I've heard horror stories on replacement cost."
Sir, Having a CVT means clutch maint. every now and then.
1) A belt is like 30 bucks or so and they wear forever.
2) Lack of maint is what costs money. Without cleaning dirt will wear the parts. IMO, in a family setting, I'd clean the clutch's every 10 hours of riding. It is easy.

Would never gamble on a Chinese carb, forums are full of horror stories of problems with them. A good rebuild kit on a factory carb is far superior! Leaving any machine sit unused will cause numerous problems, use it ot loose it is sound advice!

Well it certainly could be cleaning the clutches as I've never done that. My bad, 100%. The soil at our property is extremely sandy - gets in everything, so I feel pretty stupid right now not having done it before. I'm hoping parts aren't ruined.

I just obtained the service manual for it so will be doing some serious studying and catching up. Perhaps I can find the specs for the sensor and find a suitable auto part alternative. Thanks everyone and please keep it coming if you have more thoughts.

-Bill

"Would never gamble on a Chinese carb, forums are full of horror stories of problems with them."

Honda 350, old carb has a badly worn CD piston, new piston/diaphragm assemblies were ridiculously expensive last time I got one, so at £30 a new carb is worth a punt, and as I wrote above, it worked, job done, cheap. I don't go in for new carbs just because the old one is dirty, in fact I don't go in for fitting carb kits because the carb is dirty, but the old carb still ran badly after cleaning, and I had noticed the worn piston.

Can't say I ever clean belt boxes out until the belt goes bang, and many of our customer's Quads have 2000 plus hours on them, but muddy north west UK conditions may be different to desert US ones, and big autos like King Quads tend to have well thought out belt ventilation systems.