Craig Nipper

OBDii codes are: PO191 & PO174. Changed fuel pump twice now and still won't start. Fuel pump does not turn on checked fuses,relays & shutoff switch. Has power at fuel pump connector Any ideas??? PLEASE HELP

seniorFORDtech

heritage or new body stlye

Craig Nipper

Sorry about that new body stlye with 5.4

seniorFORDtech

let me ask you did the truck die while you were driving or did it just not start .

Craig Nipper

Came home & 20mi later went to leave & wouldn't start couldn't hear fuel pump so thought that was it.

seniorFORDtech

my first thought is the (fpdm) fuel pump driver module may be bad but let you say you changed the pump twice are you using a ford pump or aftermarket.aftermarket pumps are cheaper but you no the saying you get what you pay for.. if your using a ford pump then you need to check the power wire from the interia switch to the fpdm go to the interia switch there will be a orange wire with a black tracer using a test light turn the key on you should have power 12volts . if ok the under the truck leftside back by the spare tire is the fpdm it is a black box with a heat sink on it one connector check the same wire for 12 volts. remove it and look very closely there may be a corroded conector or the box itself may be corroded and has water entry to it. you need to look under the module for this hole.. if its rotten it needs to be replaced...the fpdm runs between the pump and the interia
hope this helps

Craig Nipper

Thanks I will have a look at it soon & yeah it's a aftermarket pump. Is this a common problem with these trucks? ...... Thanks for the help will let you know what I find.

seniorFORDtech

the fpdm is not real common but have had a few over the years..
try plugging in a new fuel pump outside the tank and check your powers..


question you say you have power at the fuel pump connector what color wire is that has power.
the connector should have 2 wires for the pump
1. pink with black tracer
2. brown with white tracer
3. yellow with white tracer goes to cluster for gauge
4. black with orange tracer is ground going to cluster

Craig Nipper

I don't remember what color wire's we tested but got power on 2 of them we will do it over & see what we get. THANKS for the help.

Craig Nipper

I pulled the fpdm & it is cracked & corroded the in side has a lot rattling around in it going to replace it tomorrow will let you know what happens. Thanks for the advice.