rwc2010

I have this 95 F-150 with the 300 inline 6. I replaced the fuel pump and replaced the fuel filter 3 times since the pump was replaced only 4 weeks ago. Sometimes it runs great while other times it runs sluggish like it has a real bad miss. I've changed plugs and wires. I have replaced the only vacuum hose that I found to be bad and nothing is helping. Has anyone had problems with this or can point me in the right direction? Any help will be greatly appreciated.

windshear

You may be getting into phase separation if the fuel you're burning has ethanol. Ethanol combines with water in the fuel, but only to a point. Once saturation is reached, the ethanol and water separate from the gasoline and collect at the bottom of the tank. This makes for rough running and loss of power.

I got into this with a Dodge Neon. Like you, I thought it was a fuel system problem. I was in the habit of topping off the tank when it was about half full.

The solution was to burn the fuel tank down nearly empty before refueling. Running was very rough the first time I did this. Adding some dry gas seemed to help.

After doing this a few times the car straightened out and ran fine. To keep the problem from recurring, I then held off refueling until the gauge indicated 1/8th tank remained...or the fuel warning light came on. I also added a bottle of STP fuel additive (the cheap stuff...$2.97 for 3 bottles at Walmart) at each fill up. The problem never returned.
Bob

95beast54

i aso have a 95 4.9 5 speed. goin about 50 mph and givin it gas it will kinda sputter and gain a little speed i clean the air system checked plugs and wires also cannot figure out what is . its making me get bad mileage and losing alot of power sometiems it would idle really rough and high but once i cleaned the throttle body and air filter and ran some sea foam it quit noww it just sputters when driving. let me know if you figure something out thnks

52f1

wiring can be it. look around for open wires!!!