Hi, so last weekend on a camping trip my 15 yr old son sunk our 06 sportsman 500ho EFI in water. He continuously tried to start it after, before I got there (not good). When we got it back to the campsite I drained it, all plugs. Pulled spark plug and cranked it, then added some seafoam to the tank. It started for a few seconds...... Now it's home & I've flushed all fluids and installed a new spark plug. It has good spark, good compression, but only starts if I feed it fuel. Does anyone know how the EFI system works? It's my first one, I'm used to a regular carb. Thank you in advance! For any EFI knowledge on these.

 

Check the fuse/relay for the fuel pump. May have blown one or the other. If that's all good start with the basics. Should hear the fuel pump engaging/priming when you turn the key on. If all good there then check fuel pressure as the pump may be bad.

 

Pop the top off the throttle housing and check for any moisture. Water can short between the etc contacts and the only way it will start is to give it throttle. Had a couple like this that were swamped. Plus make sure you have 2 mm clearance between the contact points. If it's less you can take up throttle slack on the cable adjuster down from the housing. Not a bad idea to blow out all connectors,fuse block and use some electrical grease.