troubleshoot 94 Mustang gt

I would try starting it again. If does not start immediately try the starting fluid.
If it starts or kicks then assume you have a fuel problem.

Next measure the fuel pressure.
If not within spec, listen to hear if the pump runs for a second as soon as you turn on the key.
If it does not run, verify you have power at the pump for the second after you turn the key.
If the pump runs, change the fuel filter, look for damage to the fuel line and check your pressure again.
Still low or no pressure- either first replace the pressure regulator or buy a major brand name pump (preferably Motorcraft) and pick up filter. I have seen aftermarket off brand pumps last less than 6 months. I would think the pump would be more likely to go bad before the regulator.

If you find an electrical issue, reach back and I may have some suggestions. Good luck.

At what point will you recognize that this is a 4.6 forum?

Noobz347 said:

Click to expand...

What the effff? You moved this thread didnt you.....?

The fuel pressure check sounds like really good advice to begin with based on your initial info. If it's starting / running with starter-fluid, then it seems like the ignition system is functional - good news because I think these old ignition systems are more difficult to diagnose. As dcm0123 mentioned, do you hear the pump prime at key-on? Can you check fuel pressure at the fuel rail? If you don't have experience doing this sort of test, it's not difficult, but please be very careful because you're dealing with fuel under pressure and there's a lot of potential for fuel leaks / spray. It sounds like you may have an intermittently failing fuel pump, failing pressure regulator, clogged filter, or an electrical issue related to the fuel pump (relay, wiring...). A fuel filter swap may be a quick first step if you're ready throw a cheap part at the problem, especially if it hasn't been changed for a long time.

Keep an eye on your battery voltage while running these tests. Repeated / extended cranking can suck down the battery quickly and it becomes extremely frustrating to deal with a dead battery in addition to the original problem. You may have to pause and charge the battery after a couple rounds of tests. I wouldn't recommend keeping a battery charger hooked up while checking fuel pressure or during any other fuel system test that can result in a fuel leak.

It might help us to know your general experience level with automotive work. If you're using starter fluid, which is fairly dangerous on it's own, then you've probably got some good foundation in engine work to begin with.

Good luck! I hope it's something simple to diagnose and fix.

One other thing to throw in on the fuel system is the rubber hose between the fuel pump hanger bracket pickup tube and the fuel pump itself. These can rot out over time and crack which in the beginning will cause some weird issues and then in the end a no run situation.