Modded Mustang Forums banner

1 - 15 of 15 Posts

·
Registered
Joined
·
5,556 Posts
Discussion Starter #1
ok so the 2 big things i have wrong fuel pump wouldnt turn on and engine wouldnt turn over...

wel i got it to do both but nither at the turn of the key....

i was able to jump the selnoid and get it to turn over so i am pretty sure i have the wires hooked up wrong to the selonid.

i took the drivers seat out and was able to jump the hot wire to the two pink ones that go to the fuel pump and it turned on and pressureized the system to 30 psi now i have to figure out if the relay is bad or if the wire that triggers the relay is bad. how does the system shut off is it controlled by the computer or inside the fuel pump? or does it run constantly while the car is running?
 

·
Registered
Joined
·
4,781 Posts
Did you get a key on 12V pulse at the relay activation wire when cycling the key?
 

·
Registered
Joined
·
5,556 Posts
Discussion Starter #3
Did you get a key on 12V pulse at the relay activation wire when cycling the key?
what do u mean?? that it isnt constantly 12v... the voltage would go up and down...
 

·
Registered
Joined
·
5,556 Posts
Discussion Starter #4
or do u mean the green and i think yellow wire? i wasnt getting anything from that as far as power..
 

·
Registered
Joined
·
146 Posts
when you look at the relay plug there should be 1 wire that is constant hot it is a heavier gauge then you will see another wire same gauge that feeds the pump there will be 2 smaller gauge wires 1 is a ground the other get power when the key is turned on to cycle the fuel pump when the engine is running that wire will have power on it to keep the relay closed thus keeping the fuel pump running all you need is a test light or a meter can you can check the plug
 

·
Registered
Joined
·
4,781 Posts
the thick orange light blue wire should get a constant 12 V source

The thin red black wire should get a 12V spike for about 1 second when you turn the key from the off to the on position (this is how your fuel pump normally primes when you turn the key on).

You should get continuity with ground on the tan light green wire when the key is cycled as well.


Actually come to think of it the thin red/black wire might be positive all the time when the key is on and the ground only cycles for 1 second....not sure but you should definitely get 12V at the red/black wire for the first second when you turn the key and then maybe after that.
 

·
Registered
Joined
·
5,556 Posts
Discussion Starter #8
the orange lt blue is the constant then there is 2 pink wires that when jumped from the orange the pump turns on.. then there is a red/black wire and a green/something wire

so when the ey is on the tan/green becomes ground? ill try that out...
 

·
Registered
Joined
·
4,781 Posts
the orange lt blue is the constant then there is 2 pink wires that when jumped from the orange the pump turns on.. then there is a red/black wire and a green/something wire

so when the ey is on the tan/green becomes ground? ill try that out...
Are you listening to me?:eek::eek::eek:

You are jumping from the hot side to the pump and have verified that circuit is good. Congrats. Now you need to check the relay activation circuit. the red/black wire is the postive that turns the relay on and the green/tan wire is the ground. If you are not getting 12V at the red/black wire for at least 1 sec at key on that is your problem. If you are not getting ground for at least one second at the green tan wire at key on, that is your problem. Got it? The relay has two complete circuits. Two hots, two grounds (one ground is the pump, the other is the computer).
 

·
Registered
Joined
·
5,556 Posts
Discussion Starter #10
gotcha.. :) so ill stick my multimeter in there and see if i can get anything thanks..
 

·
Registered
Joined
·
5,556 Posts
Discussion Starter #11
ok just tested it... the tan/green one is ground the red/black one gets nothing when the key is cycled.... i think i have a bad computer... i went ahead and pressureised the system turned the key to the on position and turned the engine on and i got nothing not a ping not an attempt to start ... so i am pretty sure i have a bad computer or bad ecu harness..
 

·
Registered
Joined
·
5,556 Posts
Discussion Starter #14
Are you getting power to anything when you turn the key? Just wondering if have ingition switch (the box with the connector-not the lock cyl.) issues.

BTW, can you get to here from work???
yes i can :)
 

·
Registered
Joined
·
333 Posts
yes i can :)
What the hell is up with that??? You're on a super-anal AETC active duty base where you can get to a "forum" website-----and I can't get there from a guard base:wtf People have been saying that we're getting more and more like the active duty all the time--I just didn't know we'd actually get more anal retentive.

How's the troubleshooting coming???
 
1 - 15 of 15 Posts
Top