Ok, so I have a 1993 ford escort gt that will not pump fuel through the fuel lines. I know the pump works, I can hear it kicking on and off, and if I remove the fuel lines from the pump fuel pours out. I know the lines are not clogged, I took a high pressure air pump and blew air through the lines, but for some reason when I hook up the lines it will not pump fuel through them, after turning it over if I remove the lines they are still dry. Any ideas?
Oh, and I know that the engine is getting fire, I found a screw leading to the injectors and when I pour gas in it, it will start for just a second.
If the fuel pump is developing enough pressure the gas should shoot out of the hose. Not pour out. So it sounds like the fuel pump isn’t developing enough fuel pressure.
And here’s a word of advice. Do not install an aftermarket fuel pump. Go to the dealer and get a FoMoCo fuel pump if possible. Because aftermarket fuel pumps don’t last in your vintage of Ford.
The pump might be able to spit some fuel out. But it just sounds likely that its mostly dead. Electrically ok maybe - but just so weak as a pump that it can’t actually pressure the lines.
So I’m just guessing that you need a new pump.
well, the pump is new. The car had sat for a number of years, and replacing the pump was the first thing I tried. and when the lines aren’t hooked up fuel comes pouring out very strongly…
New pumps can be bad off the shelf.
Other than that you’re obviously missing something.
You mention pulling lines & blowing air through them - blowing air from where to where? Hook the line up at the pump. Follow the line to each coupling. Work section by section - disconnect each coupling & energize the pump until you’ve worked all the way to the fuel rail. Also pull the fuel rail & inspect.
This should be a TFI car. The ignition module provides a pulse to the ECM which then provides a ground for the pump relay.
Look at the diagnostic connector where the codes are pulled and you should see a tan wire with a green stripe. This particular wire goes to a splice in the pump relay/ECM circuit. Run a jumper wire from that wire to ground somewhere and see if the pump works. If the pump runs then the diagnosis has to go a bit further as to why the ECM is not providing a ground.
With a VOM or test lamp connected to a power source (Not ground) you should see a ground in that circuit when the key is turned on but only for a couple of seconds. When the engine is being cranked over by the starter motor you should see the ground reappear. If not, you should consider the possibility of a faulty ignition module or internal ECM circuit fault.
How about the fuel filter? Did you change it?
Thought: The system has a return (to the tank). If the return is blocked, the pump will assume the lines are pressurized, even though they may be empty. Did you check all the lines? Or just from the pump to the fuel rail?