Long crank after sitting?

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wsteele

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Test the fuel pressure using the correct procedure, KOEO (key on, engine off). Post up the initial value.

After turning off the key, document the time it takes for the pressure to leak down, and what the pressure is at, say, 5 min. intervals after key off. Based simply on the strong fuel smell I'd guess a leaky injector. If it does leak down, there is a pressure leakdown valve in the fuel pump as @avalonandl noted, so there could be other causes. Doesn't this truck have an FPCM?

When it cranks long, floor the gas pedal and that puts it into clear flood mode. If it fires right up the fuel is likely leaking into a cylinder or two after shutdown.
I agree, and yes it does have a FPCM.
 

Fless

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Considering how well-sealed the fuel and vapor system is supposed to be on these things, you most definitely have a leak. You shouldn't be able to smell any fuel at all.

There's only one visible junction in the system in that area that is part of the pressure side of it. It's in front of the tank, near the frame rail. If it's not leaking from there, then it's likely on top of the tank.

Dropping the tank isn't the easiest task, so you might wanna consider replacing the pump module when you drop it to repair the leak. If the leak is a cracked and/or corroded fitting on the bulkhead, then you'd be replacing the module anyway.

Not part of the pressure system but if the fuel pump module gasket is leaking you can get fumes from that, too. Just dealt with that on my '04 due to a failing evap test; when performing a purge and seal, the seal wouldn't hold. Like @iamdub mentioned, if you get to the point of having to drop the tank it may be a good idea to have a whole new pump module ready just in case.
 
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okfoz

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I was wondering if there was an update to this? If so what was the problem?
 

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