I've got an 09 arctic cat mudpro with EFI. Any idea why the idle is funny? Sometimes it idles good, then sometimes it can't even idle so it stalls, and sometimes it has trouble starting. I think if the ECU got wet it wouldn't start at all, maybe the injectors?? Thanks.

 

change your plug. put dielectric grease inside the boot.
check your TPS and ISC valve.

 

Thanks for the response... I have changed the spark plug and put grease on the boot, and I have also positioned the TPS correctly, I have yet to check the ISC valve.

 

did it fix your issue?