TEST 2: Using Starting Fluid To Confirm Lack Of Fuel
A quick and dirty way to check to see if a lack of fuel is causing a no-start problem is the starting fluid test.
This test simply involves spraying starting fluid into the engine and then cranking it to see if it starts.
If a lack of fuel is behind the engine's no-start problem, then it'll start and run for a few seconds (until the starting fluid is consumed).
It's important to note that using starting fluid to diagnose a fuel pump is not the most accurate way. Still, it's an effective test that'll get your fuel pump diagnostic started.
NOTE: To get an accurate test result from the starting fluid test, it's important that you make sure that all 8 spark plug wires are sparking.
IMPORTANT: This is a very fast and easy test but you do have to take one very important safety precaution and this is to reconnect the air intake duct back to the throttle body after spraying starting fluid down the throttle bore (although you don't have to fasten it). This will prevent any backfire, that might occur, from scaring the heck out of you when cranking the engine.
These are the test steps:
- 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
Open the throttle plate and spray starting fluid down the bore.
As a safety precaution reconnect the air duct after you have sprayed a good squirt of starting fluid (but you don't have to tighten the air duct). - 3
Crank the engine once the air duct is back on and you're clear of the engine compartment.
- 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 analyze your test result:
CASE 1: The engine started and ran for a few seconds. This test result confirms that a lack of fuel is keeping your Dodge Pickup's engine from starting.
Your next step is to check to see what the fuel pressure is with a fuel pressure test gauge. Go to: TEST 2: Checking Fuel Pressure With A Fuel Pressure Gauge.
CASE 2: The engine did not start, not even momentarily. This usually means that a lack of fuel IS NOT the reason your car is not starting.
Now, remember what I said about this test not being very accurate? Well, I suggest you do one more test and this is to check the fuel pressure with a fuel pressure test gauge. Go to: TEST 2: Checking Fuel Pressure With A Fuel Pressure Gauge.
Fuel Pressure Release Procedure
Before installing the fuel pressure test adapter, on the fuel rail without a Schrader valve, it's important to first release the fuel pressure within the fuel line.
Here's the procedure that applies to the Dodge Ram pickups:
- Remove the fuel pump relay from the Power Distribution Center (fuse and relay box located in the engine compartment).
- Crank the engine. If the engine starts, let it run till it until it stalls.
- Crank the engine several times or until it won't start and run.
- Cover fuel line with shop towel and disconnect it from the fuel injector rail.
- The shop towel will absorb any residual fuel left in the fuel line.
- Re-install the fuel pump relay.
- When done with the fuel pressure test, clear any diagnostic trouble codes caused by cranking the engine without the fuel pump relay installed in the Power Distribution Center.
More 5.2L, 5.9L Dodge Ram Diagnostic Tutorials
I've written quite a few 5.2L, 5.9L Dodge ‘how to test’ tutorials that may help you troubleshoot the issues on your Dodge Ram pick up. You can find them in these two indexes:
Here's a small sample of the articles/tutorials you'll find in these indexes:
- How To Test A No Start Condition (Dodge 3.9L, 5.2L, 5.9L).
- How To Diagnose Misfire Codes (Dodge 3.9L, 5.2L, 5.9L).
- How To Test The Fuel Injectors (Dodge 3.9L, 5.2L, 5.9L).
- How To Test The Ignition Coil -No Start Tests (Chrysler 3.9L, 5.2L, 5.9L).
- How To Test The MAP Sensor (P0107, P0108) (Dodge 3.9L, 5.2L, 5.9L).
If this info saved the day, buy me a beer!
