What causes your 1978 Dodge Pickup to bog down when accelerating the fuel pump has been replaced and also the fuel filter could it be that there is dirt in the line?

Answer 1

My wife's 1979 Chrysler Le Baron had a 318 engine with fuel problem that Chrysler couldn't fix. We bought it new. It would die (usually, going up the parking garage) when you would accelerate. I changed fuel pump, checked carb, and everything I could think of. If you pulled the hoses off the emmissions canistor and blew back into them the car would start and run. After $900. I finally hooked a fuel pressure guage in the fuel line going to carb. Started with 14lbs pressure and found that the pressure would decrease rapidly when accelerating. Found problem to be a one way check valve inside the fuel tank. It had fallen off. Most car fuel pumps pump the fuel until the bowl in carb is full and the float shuts it off. Then the fuel pump freewheels (limp) pumps on the cam. Chrysler changed this operation somewhere along the line. When the carb bowl is full it senses that and the fuel pump pumps the fuel right back into the tank. No freewheeling. With the check valve off the system thinks the fuel bowl is full therefore it just pumps the gas out of the tank and right back into the tank. You will have to empty the tank before dropping it. I used a small electric pump. Your truck should be easier to work on than the Le Baron tank. This check valve is a small white nylon valve about the size of a cigarette and about the same length located beside the float. It has a "Chrysler Star logo" on it but it did not show up in their Illustrated Parts Breakdown therefore no part number. Chrysler couldn't identify it and had no idea that it was there. I used 3 small nylon wire ties to secure the old one back on the plastic spagetti tube. I have seen this problem twice. The other time was on a 1978 Dodge car with a 318 engine.