85GTStangGuy
5 Year Member
These are some good looking wheels. Pretty pricy thoughToo rich for my blood.....
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Pinion Setting Tool?
What does one need this for? How does this tool 'set the pinion'?


I re-soldered the battery wire and hard wired the extension cord to the reader. I figure there's no reason it should have to come apart anyway, right?! Of course the housing wouldn't snap back together, so I zip tied it and called it good. Then I hooked it up to the car to see what kind of codes it'd throw (KOEO obviously, since the fuel pump isn't priming....) - here's what it gave me:
Just for fun, I pulled the fuel pump relay and will be getting a new one just to see if it'll take care of it before I drop the tank. If it doesn't I already have the pump, soooo....And I must point out he did not paint the tank vent valve.....just say'n....How about this, check for 12V+ at the fuel relay from the ECU power relay. My guess is you will have power at the coil pin on the fuel pump relay from the ECU relay being you got codes. The battery power pin on the fuel pump relay come from the inertia switch which is powered by the ECU power relay. Being the ECU is providing codes you should have power at the fuel pump relay unless the inertia switch is tripped or bad.
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Take a test light and put 12V+ on the alligator clip and use the probe to back probe the wire from the ECU that goes to the fuel pump relay. Turn the key on and if the test light lights up the you know the ECU is putting ground to the relay and the ECU is good in this aspect. So if you have power at the relay and the ECU is providing a ground for the coil then you need to check the output of the relay to see if power is going to the fuel pump. If you have power there then I would look for this connector just above the seam of the fuel tank behind the rear bumper cover. You can see the connector here albeit crusty:
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And here you can see that it is supposed to be a red/orange color (this is a pic from Mustang5L5’s thread)
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Disconnect this connection and make sure there is power here. If so then you know you have to drop the tank.
Take a test light and put 12V+ on the alligator clip and use the probe to back probe the wire from the ECU that goes to the fuel pump relay. Turn the key on and if the test light lights up the you know the ECU is putting ground to the relay and the ECU is good in this aspect. So if you have power at the relay and the ECU is providing a ground for the coil then you need to check the output of the relay to see if power is going to the fuel pump. If you have power there then I would look for this connector just above the seam of the fuel tank behind the rear bumper cover.


Another thing I did, though I'm not sure I did it right, was applied 12V and ground to pins 4 and 5 in the relay. I believe it should click with power applied to those 2 pins, right? It does nothing....
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"For this example:
1 - 12V+ from the inertia switch which gets its 12V+ from the ECU power relay
2 - switched ground from the ECU
3 - Constant 12V+ from the battery via a fusible link at the starter relay
4 - empty
5 - 12V+ to fuel pump
"So I just got to this. What if the light lights up with the key off but then shuts down with the key on? So, backward as you've explained?"
I am not sure what you mean by this. I am assuming you tried the test on the coil side of the relay and with the key off the test light is on and with the key on it is off? If that is the case and you have 12V+ on the clip side of the test light and you probed the wire that comes from the ECU (Tan/Light Gree wire) then I would say the ECU has an issue.
If you can disconnect the wire from the ECU to the fuel pump relay, turn the key on, check for 12V+ on Pin 3 (Orange/Light Blue) as well as the Pin that has the Red/Black wire. If you have 12V+ at both of those then ground the Pin that had the ECU wire on it and see if you get 12V+ on Pin 5 or listen to see if the pump comes on. Report back.



So is each layer loose, as in you have to build the stack each time?finally built some wheel cribs.