Skip to main content ↑ ↓
Topic: Draining gas tank (Read 1475 times) previous topic - next topic

Draining gas tank

I m trying to find an old post about jumping two wires in the diagnostic port to run the fuel pump so i can drain the old gas out.cant seem to find it can some one help me out with the post or the terminals

Draining gas tank

Reply #1 –
Its in the sti self test port... i don't know which one, but it needs to be grounded if i recall correctly.

you can also find the green relay in the trunk area and jump it there, but i beleive you need computer input to trip power to the relay.
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

Draining gas tank

Reply #2 –
Just ground the fuel pump wire in the diagram below.

1986 Mercury Cougar - 2.3T/T5 swap, TC brakes and suspension and rearend, 3" exhaust, 255 lph fuel pump, Stinger BOV, Gillis MBC @ 18 psi
2003 Chevy Suburban Z71 - Daily driver
2015 Chevy Volt - Wife's daily driver

Draining gas tank

Reply #3 –
Why not just turn the switch on?
...and there was light!

Draining gas tank

Reply #4 –
Quote from: T-BirdX3;432701
Why not just turn the switch on?
If your fuel pump runs continuously with the key on and the engine not running, you have a problem.
It means your ECU is in LOS (Limited Output Strategy) mode.

Draining gas tank

Reply #5 –
Thanks loaded87iroc that was just what I was looking for. Now i can drain the 2 year old fuel out and get the the cat purring again

Draining gas tank

Reply #6 –
Quote from: phyxius;432839
Thanks loaded87iroc that was just what I was looking for. Now i can drain the 2 year old fuel out and get the the cat purring again


chassis ground the tan / light green wire within the diagnotic connector.
turn the key forward
the fuel pump will run continuious.

so with your fuel line separated (supply side which is the one with the shrader valve test fitting), and doing the above, you should be able to empty the tank.

normally the fuel pump runs for about 1 or 2 seconds by simply turnking the key forward then times out by way of the EEC noticing there is no ignition.

softtouch is right if or ever you notice this happening and usually its only root cause is someone has jumpered out the fuel pump relay in the trunk incorrectly and screwed up the eec.