Does anyone know how to test a fuel pump on a 1984 2.5 ?

[84duke]

Does anyone know how to test a fuel pump on a 1984 2.5 ? Im not getting fuel to the fuel filter. New fuel filter , new fuel pump relay, new fuse. I do hear the pump runnig for like 2 seconds when i turn the ignition on but no fuel comes out. The car sat for awhile, I put 2 gallons of fresh fuel in. It has new plugs and wires and oil. Does anyone know what this connector is for? see pic. its on the drivers side, it has a black wire attached to it and it goes into the harness. It runs with starting fluid. thanks

[jelly2m81]

That connector is for the decklid release solenoid. To test for fuel pressure you use a fuel preesure gauge, but seeing you have already deduced that there is no fuel leaving the tank but you do hear the fuel pump run common sense tells us you need to drop the fuel tank and see what's up in there.


Probably a rotten / split hose between the fuel pump and sending unit feed pipe.

[Aaron]

i HAD THIS SAME PROBLEM ON MY 88gt. Fucking capslock sorry.

Anyways, on mine, the metal line that goes into the tank pushes into the fuel pump, and that's the feed pipe. On mine, the metal line had come out of the fuel pump, so the pump would just pump fuel up, and it'd splash right back into the tank, none of it going into that line. I'm betting this is your problem. So you will probably need to drop the tank.

[Emc209i]

Don't have access to diagrams right now, but if the ALDL port is wired the same as the later models, pin G (orange wire) is the test wire. Putting 12 volts to it will bypass the fuse and relay and go straight to the pump. If you have gas in the tank and the pump is priming but nothing is coming out at the rail, I'd suggest the pulsator has come unseated from the pump top, or there is an obstruction in the line.

[Shaun41178(2)]

Don't have access to diagrams right now, but if the ALDL port is wired the same as the later models, pin G (orange wire) is the test wire. Putting 12 volts to it will bypass the fuse and relay and go straight to the pump. If you have gas in the tank and the pump is priming but nothing is coming out at the rail, I'd suggest the pulsator has come unseated from the pump top, or there is an obstruction in the line.

this, jumper the pump from the aldl port and you should see fuel flow out of the line, if not then something in the tank wasn't hooked up right, or fell off.

Also you might want to try "priming the pump" several times to make sure no fuel is coming out. When you put in a new pump the 2 seconds to prime might not be enough to produce any real flow yet. How many times did you turn the key to prime the pump?

[84duke]

i turned the key many times before trying to start it and nothing came out of the fuel line at the front of the filter connection. Also the gas gauge did not move it shows half a tank. Would this move when you start the ignition?

[Shaun41178(2)]

turning the key simply to the on position should move the gauge if the level is less then half a tank. Perhaps you forgot to plug your sensor back in so your gauge isn't working now.

But definately jumper it at the aldl connector and you should hear it run.

[Aaron]

Why are we beating a dead horse? He said in his initial post the fuel pump primes and it has gas in it. Thus, fuel pump works.

So the problem is either a clogged line before the filter (Very unlikely), or a problem in the tank (Very likely).

[84duke]

where and what is a aldl port? and how do you jump it?

[Aaron]

It doesn't matter, we've already determined your fuel pump works. Since it primes when you turn the key on, it works. By jumping the ALDL pin, you're basically doing the same thing, except not for a couple seconds, but indefinitely. No difference, fuel should flow during the prime period as well. Sorry bro, the tank's gotta come down.

[jelly2m81]

It doesn't matter, we've already determined your fuel pump works. Since it primes when you turn the key on, it works. By jumping the ALDL pin, you're basically doing the same thing, except not for a couple seconds, but indefinitely. No difference, fuel should flow during the prime period as well. Sorry bro, the tank's gotta come down.

yep, sometimes you think this is piffle here............

[Emc209i]

where and what is a aldl port? and how do you jump it?

It's between the seats under the center console (next to the cigarette lighter.) You can get to it easily by removing the black faceplate on top of the cig. lighter or removing the entire console.

Here's what the end of it looks like (See pin "G").


If you want to be sure before you drop the tank, put 12v power to it and see if anything comes out the line after a couple of seconds. Put a gallon of gas in the tank to be sure.

[KurtAKX]

Put a gallon of gas in the tank to be sure.

Sadistic bastard. You're just telling him that to try and make his tank heavier, already knowing he'll have to drop it.... I like it!

He already put two gallons in as part of the diagnostic process.

[Aaron]

If you want to be sure before you drop the tank, put 12v power to it and see if anything comes out the line after a couple of seconds. Put a gallon of gas in the tank to be sure.

Or you could just flip the key on, and it'll run the pump for a few seconds for you.

Hear a whine? Fuel pump is good.

No gas? Tank's gotta come down.

It's not fucking rocket science. BY jumping the ALDL, all you're doing is giving the pump 12v. Same thing that happens, and is happening in your car, when you turn the key. The pump isn't going to run any different.

[Emc209i]

It's not fucking rocket science.

Neither is your idiosyncrasy. Putting oil in my engines before I start them - also not rocket science. What's your point, Aaron?

[jelly2m81]

It's not fucking rocket science.

Neither is your idiosyncrasy. Putting oil in my engines before I start them - also not rocket science. What's your point, retard?

His point is we already know the fuel pump runs, the OP stated that in the first post.

By telling him to check to see if the pump runs is redundant, and is along the lines of Piffle tech, 'my fuel pump runs, I hear it, what do I do?' Piffle answer, ' power the ALDL connector to see if the pump runs'...DUH

[84duke]

so i dropped the tank today and found a big hole in the hose that goes to the line and the pump, pump was fine but i replaced it with a new one since i was there. So now i have fuel in the line but now the injecter on the tbi wont spray gas. How do i test the red and blue wires for the injector to see if its the connector or the injector? It has spark and will start with starting fluid but theres no fuel going into the injector. Any ideas? Im so close but I just cant get there. thanks

[The Dark Side of Will]

No fuel going into the injector or no fuel coming out of the injector?
Two different problems.

[84duke]

coming out of the injector

[Shaun41178(2)]

could be as simple as a fuse, or could be the injector is clogged. If you put a test light on the injector lead, and try to crank it over, you should see the test light blink, which indicates its getting a reference signal. If thats the case, then the injector is probably bad.