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Andyrew
I wired my fuel pump with new wiring, using the coil and the positive batt with a relay and a swich to turn off the fuel pump when the key is on.

Now for some strange reason, I seem to have more power! I was driving home and I was using my normal amount of gas to go, and I have a whole bunch more get up.. I wasnt on full throttle because I think I would have gotten less power, so in my mind I was floring it.. Felt much nicer! BUT I think the drivability was a little worse, could have been my imagination.. I think my next step is to clean the injectors...

Andrew
Andyrew
btw, dads taking if for a test drive right now to see if he thinks it has more getup..

Andrew
dan10101
Sure is a lot faster than when it wouldn't run! laugh.gif

Actually, it does feel better. Less misfire. But, there's more hp left to find.

Back to the books kid.. ph34r.gif
Brad Roberts
What do you mean by "using the coil" ??

Please dont tell me you used the ignition side of the coil to power *anything* but the coil. This is a HUGE NO NO. The coil needs a full clean 12 volts to operate... adding a power sucking/amp drawing load like a fuel pump is just nuts.

I dont understand why you cant figure out what is wrong with the stock wiring from the relay board to power/ground the stock fuel pump. Its two wires...... confused24.gif


B
dan10101
The stock wiring wasnt getting power.

We are using the positive side of the coil for this. Look, it runs, and untill I can find some other way to get this thing to work, then thats what im going to use.

Andrew
p914
Does the car have electronic ignition? If it does and the original coil is bypassed for use of a torquer coil can you use the original coil for something else?
Air_Cooled_Nut
Such a bypass of the stock system is also a safety hazard. In the event of an accident the pump won't shut off even though the engine has stopped. I HIGHLY recommend that you get a safety impact switch. I bought mine from the Ford dealership and it was less than $14. It's mechanically operated and has a big red button on it to reset it. In the event of an accident (with suffecient force) it will open the circuit. Push the red button to reset it and close the circuit. The switch has three male spade terminals: Normally Open, Normally Closed and Input (or whatever that is known as in the electronic world).

I use this on my Squareback since I'm running a Holley Red Pump for my engine.
Air_Cooled_Nut
Oh hey, I guess I have some info on my web site. Go here:
http://www.icbm.org/erkson/ttt/gasoline_fi...ank.html#custom
Brad Roberts
Andrew,

This is real simple. The power wire for the stock fuel pump wiring goes to pin 87 on the fuel pump relay (relay board).

You have done the car correctly to this point.. why "give up" ?? Its seriously ONE wire stopping this from working properly.

The fuel pump wire is black and red... it goes from the fuel pump to pin 13 on the large black connector on the FRONT side of the relay board. To test and see if the wire is working TO the pump from the relay board... pull the black cover off the 14 pin connector and put 12 volts to pin 13 with the black and red wire. Put your voltmeter on on the connector for the fuel pump (below battery tray). If you dont have voltage (after applying it to pin 13) at the connector.. then there is something wrong between the connector and the pin 13.

Now step back on the relay board one more "point" (leave the voltmeter on the) on the connector. Both leads should be IN the connector. Red lead in the black/red wire slot. Put 12 volts to the fuel pump fuse and watch the voltmeter for 12 volts. If the voltmeter reads 12... move to the next "point" on the relay board which is pin 87 on the fuel pump relay. If you dont know which one 87 is.. flip the relay over and look for the number 87 and match it up to the corresponding pin on the board. Put 12 volts into that pin..look at the voltmeter. If you dont get 12 volts on the meter... then something is wrong between pin 87 and fuse. Do you see how this works ??

This is just backtracking thru the system until you find the "bad" area.

If you get 12 volts at the fuel pump connector all the way from pin 87.. then your relay is bad.

If you NEVER get 12 volts at the fuel pump connector... check the ground wire. It's part of the bundle that bolts down to the 10mm nut/M6 stud right above the relay board.


B
Brad Roberts
srfhfdg
Brad Roberts
tyjhdhg
Dave_Darling
From the sound of it, the new wiring takes power from the coil and uses it to trigger a relay, and the relay powers the pump.

This is exactly what the stock wiring does, though a bit less directly. When you use the "power to the ECU" pin on the relay board to power the pump, it is exactly what you are doing.

So congrats, Andrew--you and your dad just replicated what was already in there! wink.gif

--DD
Andyrew
QUOTE
So congrats, Andrew--you and your dad just replicated what was already in there!


yay!

As far as the safety switch, I have a relay, and I can turn the relay off with a switch in the interior of the car.

Or are you talking about a different thing.

Brad, We did all that stuff, but it just wasnt getting juice! I'll re check everything when i get some time.

Electronic ignition, I have it sitting on my bench, I have not gotten it in its current dizzy to work, the dizy might be a carb dizzy, so this weekend I think Im going to put the EI from one dizzy to another.
Currently running points

Andrew
tracks914
Thanks for the info. My car, currenty with no motor, had the fuel pump wired from the coil too, with the original wiring just hanging there. Now I know where to start to fix it right. clap56.gif clap56.gif pray.gif
Air_Cooled_Nut
The safety impact switch is for when you cannot manually turn off the pump during an emergency/accident -- broken arm, unconscience, dash crumpled under itself and thus hiding switch, in a panic and totally forget to turn it off right after the accident, etc. wink.gif
Andyrew
Would the switch still be a good Idea if I plan on auto xing the car with slicks?

Andrew
Aaron Cox
my pump turns off when you turn the key off confused24.gif isnt that enough? you have to be pretty messed up to not be able to turn off the key in an accident....
dan10101
Brad,
Thanks for the detailed checks. We'll give it another try. I went thru the troubleshooting flowchart a couple times and finally gave up. Tried replacing parts and running new wires. We'll give this a try.

As far as the switch goes, it's more an anti-theft device. If you don't know it's there no ones going far with the car. His mother saved her 64.5 Mustang from theft by using a hidden fuel pump switch.

Dan
dan10101
QUOTE(Andyrew @ Oct 29 2003, 06:39 PM)
Would the switch still be a good Idea if I plan on auto xing the car with slicks?

Andrew

Won't make a difference. Plus you'll likely be using R-tires in the classes you'll run in not slicks.
Dan
dan10101
QUOTE(Air_Cooled_Nut @ Oct 29 2003, 09:08 AM)
Oh hey, I guess I have some info on my web site. Go here:
http://www.icbm.org/erkson/ttt/gasoline_fi...ank.html#custom

Hey that switch looks good. Cheap too.

I would mount it more solid so it 'feels' the impact.

Andrew could substitute the toggle switch with this thing. Just keep a hammer nearby when he parks it. smash.gif laugh.gif
Air_Cooled_Nut
QUOTE(acox914 @ Oct 29 2003, 06:41 PM)
my pump turns off when you turn the key off confused24.gif isnt that enough? you have to be pretty messed up to not be able to turn off the key in an accident....

Huh, I guess you've been pretty lucky to never have been in an accident.
redshift
Get one of those Jet Ski things, wear it on your wrist, and if you fall out, the car circles you until you can get back in.



M
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