Hi all,
I'm having a problem with my 1997 Dodge Ram 1500 pickup (3.9L V6 Auto), I can only go about 100-160 miles before it shuts off, which is around 3/4 tank still left in the tank. I have read around that other people have had similiar problems with the sending unit and replaced it and have still had the same thing happened. Does anyone know what is causing this and how to eliminate this problem? Thanks in advance!

 

I had that problem with my truck when I was driving through Florida/Georgia/Tennesse. Mine would get down to 1/2 tank and start to sputter and jerk. But when we'd limp it to a station and fill it up, it would run great again. Turns out the fuel pump was overheating. Once we got back to Indiana/Illinois/Wisconsin, it ran great with the cool gas. I ended up replacing my fuel pump, as the pressure was extremely low even when the pump was cool.

Does the truck not run at all after it gets to 3/4 tank? Does the problem go away when you fill it back up with gas?

 

Yes, it completely dies when it reaches 3/4 tank. Once I refill it, it is hard to get it started again, but after that, it runs fine until it repeats. If I replace the fuel sending unit, it is a package deal anyways, fuel pump included. I do drive from Florida to South Carolina by the way.

 

Did you replace the fuel filter? THe filter is below the fuel pump. It was probably caused the fuel pump to overheat....ITS CLOGGED.

 

I'd say you're due for a new fuel pump then. The Florida climate seems to be kind of hard on fuel pumps....Ram ones anyway. [&:]

I don't the clogged filter would be the cause of the overheating. If it was, the problem would occur even when the tank is full. Apparently the pump is far enough gone that at 3/4 tank there is not enough gasoline in the tank (coupled with the ambient temperature) to keep the fuel pump cool. Mine would get to 1/2 before it overheated. Once the outside temp. got below 40 degrees, it wouldn't overheat at all.

And yes, the fuel filter is below the pump. Supposely there's a "sock" you can replace. Mine didn't have one. But when you go through all the work to drop the tank to get to the pump/filter, it would be a smart move to just replace the whole assembly.

 

I had the same situation, under half a tank random multiple misfires and it ran fine when you topped off the tank.

One think to look out for is make sure the fuel gauge sending unit is working before you put the tank back in.

The fuel pump I bought had a bad FGSU and had to be swapped out.