Ford 5.4 p171/174 no start

GotWood

GotWood

Sayer of Fact
Joined
Jan 12, 2007
Location
Maiden, NC
Going to work yesterday and big red van just died. It will turn over but no start. Check engine light gives a lean mix on left and right bank. Over the last couple weeks it has been harder to start in the mornings if it sets for the weekend. I've done some reading and most mention intake problem with seals or MAF and EGR. I don't think these are my problem, I think its the fuel pump. I haven't had a chance to check the relay or fuse, but I'm doing that first before I pull the pump. Has anyone had this problem before? Does my logic seem correct? I hate just replacing parts for no good reason to chase a problem.
 
The fuel pressure guage is a definate before i pull the tank, as is relay and fuse and a new fuel filter (only about a year old). From my understanding I should have 60-100 psi.
 
GotWood said:
The fuel pressure guage is a definate before i pull the tank, as is relay and fuse and a new fuel filter (only about a year old). From my understanding I should have 60-100 psi.
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Dont replace the relay or fuse do a voltage drop test or just check voltage at the pump power and ground (with it plugged up). If its low switch ground side to a know good ground, if its still low hook the ground lead back up and jumper 12v to you meters hot lead. That way you can verify power and grounds within about 30 seconds. If the fuse is blown I power pump with my hook and check amperage requirements. If you dont have a tool with an adjustable breaker you could just unplug the pump and see if it still blows the fuse. If it blows unplugged its obviously a issue unrelated to the pump. Its important to take a look at circuit design. Could have interia switch tripped or you could see a voltage drop thats related to engine controls.
 
I don't know about the vans but my father in laws 04 f150 with the 5.4 wouldn't start. Had fire but no fuel. I thought it was the pump ended up being a fuel pump control module mounted on frame near spare tire. Plastic housing cracked and moisture killed it. My research online showed that it was a very common issue even with low mileage (>30k) trucks.
 
Hoping for some good weather tomorrow and start my diagnosis between the game and work.
 
Well,with all the cold weather and a long list of other things I finally got the van fixed. I've been working out of my truck for the past week or so and it really sucked. It was as I suspected, the fuel pump. I started by checking the relay and crash cut off thing which both were good. Unplugged the pump and checked for power after getting no pressure to the fuel rail and it was good. I guess getting the fuel lines loose was the hardest part because my tool is cheap and old. I disconnected the lines in front of the tank first, which was about the only mistake because they didn't need to be separated. Once I dropped the straps with a jack under the tank I was able to just lower it and turn it to the side to do the deed. Replaced only the pump, not the entire assembly and pushed it back up and made sure it would fire before I strapped it back up. All told it only cost me $100.50. Not bad for 230k miles.
 
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