How To Test The Fuel Pump (1987-1996 Ford E150, E250, E350)

Using Starting Fluid

When I first started working on cars as an automotive technician, most of the vehicles on the road had carburetors. And the starting fluid test was the go-to test to check the fuel pump.

Even though all of the Ford E-Series van's covered by this tutorial are fuel injected, the starting fluid test still comes in handy (especially if you don't have a fuel pressure test gauge).

I do want to let you know that the starting fluid test is not the most accurate way to find out if the fuel pump is bad or not. Still, it'll give you a head start on your engine's no-start diagnostic.

IMPORTANT: To get the most accurate test result from the starting fluid test, you need to make sure that all spark plug wires are sparking before starting the test. Test all spark plug wires for spark with a dedicated spark tester if you haven't already.

OK, this is what you'll need to do:

1. 1

   Remove the intake air duct from the throttle body.
   
   You don't have to completely remove it, since you'll have to reconnect it in one of the next steps.

2. 2

   Open the throttle manually, and spray starting fluid down the bore.
   
   When you have sprayed a good squirt of starting fluid, quickly reconnect the air duct to the throttle body (you don't have to tighten the hose clamp).
   
   Reconnecting the intake air duct is a very important safety precaution in case you get a back-fire thru' the intake manifold.

3. 3

   Crank the engine once the intake air duct is back on the throttle body.

4. 4

   You'll get one of two results with this test:
   
   1.) The engine will start momentarily and after a few seconds will die.
   
   2.) The engine will only crank but not start at all.

OK, let's find out what your results mean:

CASE 1: The engine started and ran for a few seconds. This test result lets you know that the engine's no-start problem is due to lack of fuel.

It's important to remember that this isn't the most accurate way of diagnosing a bad fuel pump. If I were in your shoes I would test the fuel pump's fuel pressure with a test gauge. For this test go to: Using A Fuel Pump Pressure Tester To Test The Fuel Pump.

CASE 2: The engine did not start, not even momentarily. This test result most always tells you that the engine's no-start problem IS NOT due to a lack of fuel from the fuel pump.

Remember, this test is not an accurate way of testing the fuel pump. I suggest you do one more test and this is to test the fuel pump's fuel pressure with a test gauge. For this test go to: Using A Fuel Pump Pressure Tester To Test The Fuel Pump.

More Ford E150, E250, And E350 Tutorials

You can find a complete list of tutorials for the full-size Ford E-Series vans here: Ford 4.9L, 5.0L, 5.9L Index Of Articles.

Here's a small sample of the tutorials you'll find:

• Manifold Absolute Pressure MAP Sensor Test (Ford 4.9L, 5.0L, 5.8L).
• Ignition Coil Test -No Spark No Start Tests (Ford 4.9L, 5.0L, 5.8L).
• How To Troubleshoot A No Start (Ford 4.9L, 5.0L, 5.8L).
• Testing A Blown Head Gasket (Ford 4.9L, 5.0L, 5.8L).
• How To Test Engine Compression (4.9L, 5.0L, 5.8L).