jugliner

Fuel supply if fine. Pressure is holding after fuel pump turns off. Pressure is fairly constance when the engine is running (roughly). I'm beginning to think I'm not getting enough air mixture. I get the smell of un-burnt fuel.

Thanks for the suggestion. I should be able to get back to the UTV in the next couple of days. Checking the fuel supply is next.

I have a fuel injected UT400 that will start and idle, but surges and sputters at higher speed. It has been sitting for 2-3 months and was fine when parked in garage. I assumed it was a fuel/air problem and pulled the throttle body and cleaned it up. I've ended up replacing the injector, IAC valve, MAF Temp Pressure Sensor, and fuel filter. I've also checked the spark plug, Still surging. I reset the ECU after every component swap. I plan to pull the throttle body again and look evrything over for any visible leaks, etc. Any suggestions would be appreciated on next steps. The problem developing after sitting makes me think it should be something simple, but I'm stumped. BTW the fuel was fresh and treated with Stabil. Thanks.