2nd Gen Non-Engine/Transmission Lift Pump and Fuel Level Sender- Both dead- coinsidence?

[ILIANBG]

I just changed my stock lift pump, now relocated, started truck, and to my surprise I saw 10 psi only. After about 100 mi. I see psi dropping, fluctuating, it goes to about 6 psi when accelerating. Strange thing is it goes to about 14 when I get on the brakes. At a comlete stop, and when idling goes to about 10 again, and the same thing happens. Why it goes up when I hit the brakes?

My fuel gauge stopped working about a week ago,when I hit the bottom of tank it goes back to normal, but after driving few min. it starts dropping and gets to E. I got the new part- fuel level sending unit, and I have to install it, I hate to drop the tank. I might try lifting the bed. I'm thinking of changing the supply line to the LP with 1/2" hose as well. I will look inside the tank to see if there's any junk, that might be causing pick-up problems.

Did any of you experience similar problems. I can't believe I was carring with me a bad new Carter pump from Cummins .

Thanks for your help.

Ilian

 

[JessePayne]

recently I had a problem similar to yours. After changing lift pumps with no difference in pressure I decided to check out the fuel pressure unit. Turns out it was leaking. Problem solved. Also if you pull your tank check the screen filter on the bottom of the fuel module.

 

[ILIANBG]

Thanks Jesse, what unit is that? Is it the sender for the gauge on an electric gauge? If so, mine's not leaking, but I guess it might be bad, or on the way out. I guess I have to buy a new Westach sender.

 

[JessePayne]

i have the isspro manual sender. It used antifreeze in the diaphragm.

 

[wcoomes]

Yes, my fuel gauge died at about the same time my luft pump did. I ran out of fuel about a week or two before both died, the low fuel light did not come on so I thought I had enough fuel to get to Flying J. I ran out about a 1/2 mile away.

 

[ILIANBG]

I've never run out of fuel so far, but I guess the Westach el. sender might be bad. I'll hook up my Isspro gauge again(mechanical with isolator) to monitor post filter pressure and I'll see what shous up. I also ordered an Airdog and a filtering device to clean the fuel before it reaches the Airdog so I don't feed it with junk that could be picked up from the tank. I want to fix this once and for all. I can't deal with this crap any more!!!