Has anyone found a definite cause of the problem? I have worked on many Chinese EFI models and they all suck! There are no service manuals and specs are sketchy at best. One I worked on at the bequest of the distributor in California: the vehicle ran fine, but would stall each time stopped or would stall when the engine was revved and then the throttle was simply closed.
Replaced the fuel pump first, injector second, throttle body third, fourth was the ECU, fifth was the battery - the solution turned out to be a valve adjustment - the distributor was making suggestions and working with the manufacturer and supplying parts, but there was no written procedure and no electronic diagnostics available outside of the factory in China where it was produced. Perhaps Polaris has some information and procedures that is not supplied by the Chinese for their Chinese manufactured products.
Shop Owner and Mechanic with over 50 years experience