Hard to start hot. Problem started after 3 hour drive to Las Vegas. Starts fine cold. Runs good

mrmoto876

Fuel pressure 35psi at idle. Fuel pressure regulator working. New fuel filter. Pressure drops to 0 when motor turned off. Bad check valve in pump. Will loose about 10psi with fuel line pinched off at filter. Waiting for in line check valve. Mas air flow sensor clean and looks good. Intake temp sensor checks good with ohm meter. Coolent temp guage working. Holds no pressure in the tank! Bad fuel tank vent valve allowing tank to vent into intake ?

mrmoto876

Figured out the problem. EVAP air valve was stuck open allowing fuel vapor to be forced into motor from the fuel tank in warm weather and when motor was hot. The other 2 problems discovered during inspection was cracked vacuum hose on fuel pressure regulator and a bad check valve in the fuel pump. Last 2 issues had nothing to do with the hard starting. Installed an in line $10.00 check valve to fix the fuel pump issue.

kyfdx

Thanks for the update!