I have a 1989 ford e150 van with a 5.0 liter v8 engine. Engine trouble code listed is 83 Low speed primary fuel pump circuit failure. I have replaced both fuel pumps. It has dual tanks. No other codes exist. vehicle will idle but has NO POWER to even go up small hills. Replaced O2 sensor, IAC, TPS, and EGR. Need some input on diagnostic procedures for this problem.

 

There may be a hi pressure pump on the driver's side frame rail approx. under where the driver sits. If it has that pump , it could the cause of the problem.

Fuel filter was replaced at time pumps were changed ?
If we suspect a fuel supply problem, a fuel pressure gauge is connected to the fuel rail on the engine to verify if fuel press is within spec.
30-45 psi.

 

On some of them the fuel filter is hidden inside the frame. You can find it looking for it but might not notice it otherwise.

 

Rusty, Baker, I did find the fuel filter you were referring to on the frame rail below the drivers side seat. Are you suggesting that the filter may be plugged causing the fuel pressure to be to low to accelerate?

 

With a code 83(electrical issue), I would look for a wiring issue to the pump(s) or a problem with the relay supplying power to the fuel pumps, which is a common problem..You could also hang a fuel pressure gauge to verify pressure, situate it so you can monitor fuel pressure as you go for a drive and work the engine.I would expect a lean code being set if the filter were obstructed.