I have a 1996 2500 4x4 and I have had a problem where if I have a bump that I have to back up over and give it a little more gas than normal the truck will cut off, then when you start it it run rough until it clears up. Is this a sign of a lift pump going bad. It has 145000 miles on it.

 

I can't help you; but you might try and post this in the 12 Valve Engine and Drivetrain forum. You might get some bites there.

 

Whoa, how did we mods miss that one.

Movin' on up.



phox

 

What's your idle speed?

 

Idle speed is at 750 to 800 and the truck gives no other problems. The fuel filter is only about 2 months old so that cant be the problem.

 

I would suspect the overflow valve, just replace it.
Best price here.
Precision Diesel Injection and Turbo Inc.
Marty Tompkins
888-734-7349
$27 + $5 shipping and handling.

 

What does the overflow valve do. Is it had to replace.

 

The way I understand it, the overflow valve regulates the fuel pressure for the fuel pump. When you open your hood, look just to your right at the front of the engine, you will see the pump. Between the pump and block there is a fuel line. Where that fuel line is attatched to the pump is the overflow valve. Just unscrew it and screw in the replacement. Real simple and easy job. Just don't bend the fuel line and you will be fine.
Tom

 

The OF valve is probably the single part on a 12 valve that wears out most often. Luckily replacement is very easy and cheap if you get it from the source I mentioned. Dodge will soak you.
All you need is a 3/4'' or 19mm open end wrench and a couple of rags. Stuff the rags down in-between the block and injection pump just so you don't lose the washers (gaskets). Trade the new valve for the old one, the new one may look different, no worry. Don't bend the line to remove the OF valve, occasionally on some trucks the valve will hit the manifold before it comes out. If it does just file or grind the cutout on the manifold till it comes out without bending the line. If you bend the line I guarantee you will have a tough time getting the new valve in.

Bottom left in this picture is the oil fill cap