I have a early 99 250 with 7.3 and 6-spd manual. It has been straight piped, has a DB tuner, the injectors, glow plugs, wiring harmess and fuel filter were replaced about a month ago.

I love this truck, can't stand to be without it and it is quickly becoming my daily driver. I've owned it for around 5 months now. On monday I stopped for fuel but when I got back on the expressway it felt like it was running under a little bit of a strain that I wrote off as maybe poor diesel fuel. On my way home from work tuesday evening it was still running the same way, when I pulled in to the neighborhood it started skipping and sputtering and I barely made it to the house. We figured out wed that it was the fuel pump, I needed the truck because my car was in the shop at the same time. I had no choice but to go to advance auto (airtex) and get a pump, it was 7 pm. After we installed it, primed the system it fired right up and had a miss for a few minutes but it went away, figured air was in the system. It ran fine all day yesterday until last night it started skipping and sputtering again, I was under a quarter of a tank so I put some fuel in it hoping maybe the gauge was off and it was running on fumes. The truck ran the same way for a mile or two in stop and go traffic then suddenly started running fine again except it has that "strain" feeling again and a lot of banging/panging.

Is it possible that I bought a bad fuel pump that went out or is on it's way out within 100 miles? Could it be sucking air into the system and that is what is causing the banging? One more thing is my alternator went out this week too, could something have taking both it and the fuel pump out or is it probably just a coincidence? I really don't know much about diesels but have learned a lot from reading on this forum the last month or so, finally decided to join it. Thanks for any help in advance and sorry so long!

Oh yea, there are no trouble codes either and the guy I bought it from had the tank and stainer cleaned just before I bought it, about 5000 miles ago.

 

Have you checked your valve cover wiring harness connections (the one under the valve cover)? I had a similar intermittent issue due to a loose harness connection. Ford sells a retro-fit part for less than $10 that locks the connector together. If you've never removed your valve covers before you're in for a treat trying to get the drivers rear bolt out

 

More then likely you have an issue in the tank. There is a set of screens in there called a mixing chamber that over time get plugged. More so when you run the tank low all the time.

Get a fuel pressure gauge and watch the fuel pressure.