So my 3.5 Eco boost fuel rail pressure leaks off after the truck sits for a while. The low pressure fuel pump then sometimes can take 3-4 minutes to pump up and shut off before the truck will start again. If I don't wait until the LPFP shuts off it won't start. I believe the pump is ok because the truck runs fine after it starts... What's the most likely cause?Owner of Fast Leroy's Bar and GrillLiquor up Front, Poker in the Rear
Reply:Pressure regulator or fuel injectors are leaking down.www.georgesplasmacuttershop.comPlasma Cutter and Welder Sales and Repairs--Ebay storeTec.Mo. Dealer Consumables for the PT and IPT torch's
Reply:
Originally Posted by mechanic416
Pressure regulator or fuel injectors are leaking down.
Reply:
Originally Posted by Fast Leroy
Thanks, any way to troubleshoot to know which for sure?
Reply:There should also be a backflow preventer/check valve in the fuel pump IIRC. If it fails, it will bleed back down into the tank. But it should also exhibit hard starting, and possible low fuel pressure too.