Engine Turning But Not Starting

[1976pianoman]

Hello guys. Can someone here walk me through the troubleshooting steps to diagnose this issue? This 98 Ford Explorer Sport is turning over but will not start. I don't want to jump into a fuel pump repair without ensuring something else isn't going on. The vehicle did run out of gas and has been refueled with 1 gallon via a gas can. I would swap out a relay to ensure this was not a relay issue but I don't know which relay is which. Thanks.

 

[masospaghetti]

The relays and fuse diagram is provided in the owner's manual.

Can you hear the fuel pump prime when you first turn the key?

Is there pressure at the fuel rail? (You can check this using the shrader valve on the fuel rail, passenger side. First test: Use a small screw driver and press the valve pin down and see if fuel comes out. Be sure to wear eye protection, If there's fuel, you can hook up a pressure gauge to make sure there's enough of it to start the engine.)

 

[koda2000]

Which V6 engine do you have?

Possibilities are:
Bad fuel pump relay
Bad fuel pump
Bad wiring or tripped inertia switch
Loose connection or bad crankshaft position sensor
Camshaft position sensor (some here have claimed)

If SOHC V6 - timing chain may have jumped time

Depending where you live, squirrels and mice may chew through wiring.

Simplest test for fuel pump related problem is to squirt about a 3 second blast of starting fluid directly into the throttle body and see of the engine tries to start. If it does you're not getting fuel. If it doesn't you may have a spark or timing related issue.

 

[1976pianoman]

Simplest test for fuel pump related problem is to squirt about a 3 second blast of starting fluid directly into the throttle body and see if the engine tries to start. If it does you're not getting fuel. If it doesn't you may have a spark or timing related issue.

You said "tries" to start. If the problem is indeed fuel, should it actually start (briefly) or just get closer to starting after spraying starting fluid into the throttle body?

Also, do I just spray directly into the throttle body air intake? Does the throttle have to be open? If so, can I manually open it with the ignition off?

Thank you.

 

[koda2000]

You said "tries" to start. If the problem is indeed fuel, should it actually start (briefly) or just get closer to starting after spraying starting fluid into the throttle body?

Also, do I just spray directly into the throttle body air intake? Does the throttle have to be open? If so, can I manually open it with the ignition off?

Thank you.

Assuming you don't have a fuel pressure testing gauge (and don't want to buy or rent one) using staring fluid is a quick and inexpensive way to test for a "no fuel" issue.

I prefer to spray the starting fluid directly into the throttle body. Spraying it into the intake tube is probably not good for the tube material. With the intake tube removed, you'll see a small hole in the brass throttle plate that makes it easy to spray the starting fluid right into the intake manifold (which is where you want it to go). Depending on how much fluid you spray in (I don't recommend more than about 3 seconds worth) the engine may start and run for a second or it may only attempt to start. If you have a helper (someone to spray and someone to crank) you may be able to keep the engine sputtering along, but that's not really the objective. You're just looking for a sign of life, indicating the engine was not receiving fuel (and spark) normally.

If the engine "kicks" using the staring fluid, your next step is to find out why it's not getting fuel (suspects: bad fuel pump, bad fuel pump relay, tripped inertia switch, clogged fuel filter, a blown fuse, a PATS issue). You've got to work through it.

If the engine does nothing using the staring fluid your next step should be to determine if you're getting spark, but one thing at a time.

 

[Turdle]

Follow this, to the letter. do not make assumptions, perform all tests.

How to: - Ford Explorer Engine No Start Procedure

 

[1976pianoman]

I was able to start the engine using starter fluid.

I switched the horn relay with the fuel pump relay yet I'm still not starting.

I checked the inertia switch and it is not tripped.

I do not have a fuel pressure gauge, yet even without one, can't I still possibly narrow this down further by checking the pressure at the shrader valve on the fuel rail? Should the fuel squirt out or just drip out? Because I believe it might only be dripping out based on my original observations weeks ago.

Thanks.

 

[J_C]

Personally, if I had it run out of gas, then this, I would put more than a gallon in, in case there is crap or bad gas still sloshing around the tank and it's still a bad mix by being diluted by only a gallon of fuel.

However, once you have turned the key to the run position, without trying to start the engine, the fuel should squirt out of the fuel rail valve with quite a bit of force, about 35PSI worth. Given the vehicle's age that PSI value might drop the longer it sits, but should not drop quickly, except of course that you've just relieved some of the pressure by pressing the valve in, but it should get back up to pressure by just cycling the key off and then back to the run position.

As far as that goes, if you hold the fuel rail valve down until all pressure is relieved, then cycle the key as described above, you can then push in the valve again - if it has built up pressure again to squirt more fuel out, then your fuel pump is at least running, which tells you there is power getting to it.

If the fuel pump does seem to be running but only a dribble, then I would start to suspect that running the tank down has put sediment into the line and clogged the fuel filter or possibly only the strainer sock on the pump.

 

[koda2000]

OP - If it started on the starting fluid but not w/out it you obviously are not getting fuel. The good news is that spark and timing appear to be okay. I don't know what you expect to see using a fuel pressure gauge. It's not going to show enough pressure for the engine to run. As said, it should be about 35 PSI at the rail. In a pinch you can even check that with a tire gauge.

The fuel filter would be next on my list, but it seems like your fuel pump is not doing it's job. Do you hear it run for about 2 seconds every time you turn the key to the ON position? I've had to replace the fuel pumps on every one of my Expl's and Mountaineer's so it's a pretty common issue. BTW - Personally I've never found any dirt or rust in any of my fuel tanks, but it can happen. Always good to check.

In my experience the Ford OE fuel pumps life spam is around 175k-200k, so anything over say 150k and your living on borrowed time.

 

[Turdle]

If this truck is parked pointing downhill, you might just need a couple more gallons of fuel. One gallon added might not do it.