How To Test The Fuel Pump (1994-1999 2.0L SOHC Dodge/Plymouth Neon)

Using Starting Fluid To Check For A Lack Of Fuel

The starting fluid test is one of the first tests I learned when I began my automotive repair career. Although it's not the most precise way to test the fuel pump, it will let you know if the engine isn't starting due to a lack of fuel (like when the fuel pump fails).

Another important thing you should know about this test is that you first need to check that all four cylinders have spark. You can easily find out by testing each spark plug wire for spark (as a helper cranks the engine). Once you've verified that all cylinders have spark, you'll be ready for the starting fluid test.

OK, here are the test steps:

1. 1

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

2. 2

   Manually open the throttle plate and spray starting fluid into the throttle body bore.

3. 3

   Quickly reconnect the air duct to the throttle body (no need to tighten the hose clamp).
   
   NOTE: Reconnecting the intake air duct is a very important safety precaution in case of backfire through the intake manifold.

4. 4

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

5. 5

   You'll get one of two results:
   
   1.) The engine will briefly start, run and then shut off after a few seconds.
   
   2.) The engine cranks but doesn't start at all.

Alright, let's figure out what it all means:

CASE 1: The engine started and ran for a few seconds. This confirms that the issue of your vehicle cranking but not starting is due to a lack of fuel.

I suggest your next step should be testing the fuel pump pressure with a pressure gauge. For this test, go to: Fuel Pressure Test With A Gauge.

CASE 2: The engine did NOT start, not even briefly. This indicates that a lack of fuel is not the reason why the engine won't start.