OFV?
 

My first diesel is this 98 Dodge 12v Cummins 2500 4x4 it has been trouble free for over a year. The previous owner spent lots of money on it, so most of the upgrades are done, turbo, injectors, trans work, gears, fuel plate, exhaust... It is currently parked in my drive way. It starts and runs good, but dies by the time I get to the end of my street, and will not start back up for about 20 minutes. When it dies out it starts sputtering like a gas engine does when running out of fuel. I have changed the fuel filter. I have noticed a decrease in fuel economy and some additional smoke recently. Any help would be appreciated.

i don't know much about 98 Dodge but somewhere in here someone explains about the same symptoms on a diesel Silverado. Practically, the answer is bad fuel pump, or no power to fuel pump because of OPS.

12 valves don't have an electric fuel pump. It would be beneficial to try to get what your fuel pressure is.

what (where on the p7100 pump) is the best way to check the pressure? Should I just tap one of the banjo fittings? I tried to stretch the spring on the OFV and it still does the same thing runs good till I drive down the road.

Yeah, you can tap one of the banjo bolts on the fuel filter housing.

Your losing prime somehow. It could be a bad overflow valve, pin hole in a line, fuel heater leaking, fuel filter or prefilter getting clogged. I would start with the pre-filter and deleting the fuel heater.

I have replaced the fuel filter, is there another filter somewhere? No leak. I am goning to tap the banjo fitting and hook up a psi gauge.

I believe the '98 12 valves have a pre filter. Fuel Pre-Filter Cleaning on Ram/Cummins when you clean this it a good idea to get rid of the fuel heater ‪Dodge 12 valve Cummins fuel heater delete.‬‏ - YouTube.

Fuel pressure is where to start first. At Idle 17-22psi.

How to check fuel pressure on a 12 valve - Dodge Cummins Diesel Forum

If your looking for an OFV Tork Tek is the ticket. Best Over flow's made in my opinion. They also sell a snubber to hook up a fuel gauge as well.

TORK TEK CUMMINS ADJUSTABLE OVERFLOW VALVE OFV010 - Tork Teknology

Good luck.

Thank you. I have ordered the Tork Tek OFV020 and fuel snubber. Once I have the PSI reading I will post. Also going to look for the pre-filter to clean it.