Engine/Transmission (1994 - 1998) need help!

[Sheepherderspecial]

ok i give up. i need help figuring this out. over the past four months, i have had an intermittent problem with the truck acting like it has lost prime. i have replaced all the hoses from the lift pump to the injection pump. strectched the overflow spring back out. i have 20psi now at all times. what is next. it may sound strange but it seems to only do it if i let it get below 1/2 a tankfull. what is going on? usually it will not start until i crank on it for a while. but today it fired right off, ran fine for 2-3 min then sputtered and died. cranked off and on for about 5 min then it fired up roughly and smoothed out. im out of ideas. thanks in advance.

Eric Bloom

 

[REFLOYD]

mine was doing the same thing then i had the idle adjusted back to 750rpm in gear with ac on and now it is fine.

 

[bmoeller]

Fuel pressure is low. Should be 18-24 psi at idle, 28-36 at 2000 rpm with no load. May need a new lift pump. Or may either have a hole in the pick-up in the tank, or something floating around in the tank that is covering up the intake in the tank.

 

[Howard Durand]

Maybe a crack or hole in the pickup in the fuel tank?

 

[BigPapa]

What about the fuel heater? Lots of leakage potential there.



Scott

 

[pwerwagn]

I had problems with my OF valve leaking... one of the gaskets was bad. Did pretty much the same thing you describe. I have no idea why though.

--Jeff

 

[cojhl2]

If the return line somehow gets above the fuel level, it allows drainback to the tank.



My guess!!

 

[Sheepherderspecial]

ok thanks for the info. as soon as i can get the truck in the shop(pulling sled in the way now) i will see about pulling the sending unit out of the tank and check there. and i will recheck the fuel pressure at the same time. what is the easier way to get the pickup out, raise the bed or drop the tank?

 

[Tom C]

Another thing to check is the shut-off solinoid.

 

[McLaughlin]

Just a thuoght but I'd suspect a hole/split in the pickup line in the tank if it only seems to happen when less than 1/2 full. My thinking is that if it is more then 1/2 full the hole/split is covered so no air is sucked into the fuel line. If it is less than 1/2 full air gets taken into the fuel system.

 

[Ol'TrailDog]

If you end up dropping the tank there is a fix for the fuel sending unit that is simple and cheap to do. Basically replacing the plastic spindle with metal and a keeper (can't remember the name of the doodaw). A search on the 2nd gens forum should have info or the www.dodgeram.org site has the fix with pics.

 

[RHARVEY]

Dont rule out the lift pump itself... I had something like that happen to mine. The pump would bleed down overnight or loose prime. I called Cummins tech themselves and that was the first thing out of his mouth. Replaced the lp and it has not given me another problem and that was 110k ago. .



Rick

 

[JSienkowski]

I replaced my LP and am still having the same issue-will have to investigate the pickup/fuel line angle.