My Durango long-cranks if it's been sitting for a day+. A couple on-only key turns to prime the pump before starting lets it start as usual. If it's sitting for a few hours, it starts normally too. I looked at the FSM and see there is a Fuel Pressure Regulator/Filter on top of the tank. I also see that part is separately available. Does anyone know if that unit also has the leak-back check valve?

 

Are you sure it's draining back and you don't have a leaky injector? There might also be a small leak somewhere.

 

True, could be injector or real leak, forgot those scenarios. I know when it does start, there is no 'too much fuel in one cyl' symptoms, instantly runs smooth. There is also no fuel smell in the closed garage where it lives.

Per the FSM, it's apparently normal for the pressure to go to zero overnight as things cool, but the lines should stay full (check valve working), so a simple key turn makes almost instant full pressure. That's why I thought check valve.

 

from tsb 999922683 - Hard start : Long crank time

Fuel pump is equipped with an outlet check valve that is an internal component in the pump

 

Thanks for finding that. I guess just live with it if that's the only fuel pump related issue. I did fine inline fuel check valves foe less than $10, specifically meant to prevent flow back. I might look into how to get one super close to the tank output. It's not urgent. Thanks again.

 

Or you could just turn the ignition on, count to 3 or 4 and then try to start. That may help.

 

That's what I've been doing if the Durango has been off a couple days. If I drive it once a day, it starts quickly. As I said, it's not debilitating or urgent, just a retired guy with plenty of garage time available wanting everything perfect.

 

the pump is 18 years old...if your luck is like mine...the pump would fail 2 weeks after you splice in the check valve.

 

I might not be leaking to the outside, but leaking into the intake port and causing the hard start. If you disconnect the rail with injectors still attached and place them on paper towels, then turn key to activate pump, you might see one dripping. Do you get a puff of smoke sometimes when starting?

 

yep that works and is a good method. I have a quick connect adaptor with a shut off lever on it. I connect it at the fuel rail and and fuel supply line....this allows me to isolate the rail from the supply line. if the fp gauge drops with the lever closed...you know its the injectors and not the check valve. your method isolates the bad injector.