HI All,
Those Dam Gremlin's,
I was on my way home from work all was fine, Stopped at the scrap yard to take a Browse through the STUFF out back, I was there about 20 min, Got back in my truck started her up the truck ran sluggish, I noticed the fuel pressure was 0 , I pulled over to see if I could here the pump running,, NO it was not,, Check pump fuse, it was OK, Pump relay would click when removed and put back in, After about 40 min of checking stuff I decided to see if I had enough wire in my tool box to try and jump the lift pump, I did have, and the pump came on truck started right up,, NOW to get home. Finally got home and after some diagnosis ( I had no Manual) I found that there was NO Ground at the lift pump. I have an extra ECM so I tried that,, No Better. SO I ended up putting 6 inch jumper from the lift pump to the frame of the truck, I drove to work this morning 28 miles and all was fine. I thought the ECM controlled the ground for the fuel system I MUST be wrong, So I am going to go to the dealer and borrow a manual on the way home. More diagnostics when I get home.
If any of you out there have any idea's of what this could be, It lost its ground somewhere maybe a splice gone bad. Of course I thought right away Injection pump BUT I drove 28 miles to work today, with no problems. I HATE when that happens.

Thanks.

 

The fuel pump relay controls power to the VP44, and the ECM controls power to the lift pump.

If you run an aftermarket lift pump through a relays you need to supply the ground to the lift pump yourself, either through a bracket or by wiring the ground. (Depending on the model of the LP)

 

However its been working for the last 5 years something changed last night on the way home, hanks for the reply, I have been trying to move post I think I put it in the wrong category.

But yes I do have Power going to the Lift pump, Yes its aftermarket, Its been in there for around 5 years most likely longer as the older I get the faster they go by, When I get home tonight I will look for maybe a broken wire in the harness to the lift pump.

 

Seek the simple things first.

Pump needs +12V and ground to operate. +12V and ground need wiring. Check the wiring, a rodent needs just one bite to disconnect something.

Since the pump works when power and ground is there- pump OK, so lots of money saved.

 

AWESOME, Thanks for the replies, Its amazing how that New England corrosion just eats it up,, Traced it down to a corrosive connection at the battery, New connectors and some wire brushing and NOW its back to normal.

Thanks again.

 

that you got it solved