For about the last 3 months every time I get below a quarter tank of gas in my 94 ram 1500 4x4 5.9 motor starts chugging like it is running out of gas. Truck has about 207,000 miles. If the tank is full or above a quarter runs really well but I'm only getting about 30-40 miles per quarter tank which is very low because before I started having problems I was getting about 80-90 depending on city or highway driving. Have asked a bunch of mechanics and nobody has a clue on why it is doing this. All help is grately appreciated.

 

There might be an issue with how the fuel pump pickup is placed vs. how the sensor is setup. This would require a fuel tank inspection, probably needs a cleaning by now anyway. Also verifying how accurate the gauge is. When it starts chugging like that it is pretty hard on the fuel pump too, so maybe a replacing it might be worth it. There might be water in the tank also as it is heavier than gas.

 

I was going to take out pump and make sure the sock was clean. The pump runs fine just when it gets low and never had issues with the gauge. Going to clean tank when pump is out. What would be the best thing to clean tank out with.

 

Just draining it completely, and maybe sucking out any crap you find on the bottom, will be adequate to the task.

I wonder about the gauge accuracy as well..... Wonder if you are just running out of gas at a quarter tank.

Have you had a look at your plenum yet? Poor fuel economy is a sign of it being blown.

 

Just did plenum gasket about 3 weeks ago did TIming chain and gasket last week. When it has acted up and have got to the gas station it only takes about 15 gallons to fill max that's why I don't think it's the gauge.

 

You might just try and add a bottle of seafoam to test for crap in the gas tank. Maybe carry a jerry can full of gas to help insure that you don't have problems on the road. For starters that might be easier than tearing into it.