Draining fuel tank - no PCM
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Joined: Jan 2017
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From: Central Pennsylvania
Draining fuel tank - no PCM
I am installing a ECS Stage 1 Fuel pump and that requires drilling a hole in the Driver Side tank. My PCM is also at ECS getting a base tune. I made sure I was just about empty before starting my project. I was on 'reserve'. I planned to jumper the Fuel Pump Relay and run the rest of it out into a gas can by tricking the pump - shouldn't be much there.
However... Will this method even work without the PCM installed? I don't want to attach the battery and try it in case I'll fry something - just my luck.
If NOT possible - how do I get the rest of the fuel out without the pump?
TIA
However... Will this method even work without the PCM installed? I don't want to attach the battery and try it in case I'll fry something - just my luck.
If NOT possible - how do I get the rest of the fuel out without the pump?
TIA
Safety Car
Joined: Jun 2017
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From: North Georgia, USA
It should work, but personally, I wouldn't power up the entire car to do this.
Disconnect the battery entirely. First disconnect negative cable. Then disconnect positive cable.
Install jumper wire from positive battery post directly to fuel pump power at fuel pump connector, or at the fuel pump relay. The power to the pump is either 30 or 87 terminal of the relay. It's the one out of those two that doesn't have continuity to the positive battery terminal. You can check continuity that way with the battery entirely disconnected. Applying power at the relay terminal or at the pump wiring harness will not power up anything else in the car. Then connect negative battery cable to ground.
Or, you unplug the connector at the fuel pump, and you can jumper to connect battery power and ground only to the pump. If you unplug it, use two jumper wires, don't connect the negative terminal for the car.
Disconnect the battery entirely. First disconnect negative cable. Then disconnect positive cable.
Install jumper wire from positive battery post directly to fuel pump power at fuel pump connector, or at the fuel pump relay. The power to the pump is either 30 or 87 terminal of the relay. It's the one out of those two that doesn't have continuity to the positive battery terminal. You can check continuity that way with the battery entirely disconnected. Applying power at the relay terminal or at the pump wiring harness will not power up anything else in the car. Then connect negative battery cable to ground.
Or, you unplug the connector at the fuel pump, and you can jumper to connect battery power and ground only to the pump. If you unplug it, use two jumper wires, don't connect the negative terminal for the car.
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From: Central Pennsylvania
Thanks for that quick reply - I'll look around at all that. Mine is a late '03 with the C6 fuel system so the pump and wires are in a bad spot for easy access. If I can power the pump from JUST the relay then - YAY!! Do I still have to turn the key to 'Run'?
Such a NOOB but learning.
Such a NOOB but learning.
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Joined: Sep 2013
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From: Cape Coral, Florida
Thanks for that quick reply - I'll look around at all that. Mine is a late '03 with the C6 fuel system so the pump and wires are in a bad spot for easy access. If I can power the pump from JUST the relay then - YAY!! Do I still have to turn the key to 'Run'?
Such a NOOB but learning.
Such a NOOB but learning.
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Joined: Jan 2017
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From: Central Pennsylvania
Diag - I was hoping I would hear from you. I printed that same pic and took to the O.R. Then, my head started doing what it always does and the PCM thing entered the room. Just a simple Panic Attack - I was gonna have a hose running and 2 fire extinguishers next to me....
I'll let you all know how much gas I really have when on an '03 Z is on 'reserve'.
Thanks to BOTH of you for the input - this place has SO MUCH talent. Never ceases to amaze me.
I'll let you all know how much gas I really have when on an '03 Z is on 'reserve'.
Thanks to BOTH of you for the input - this place has SO MUCH talent. Never ceases to amaze me.
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Joined: Jan 2017
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From: Central Pennsylvania
Well, I got about 1/2 of a 5 gal can. Then it started sucking air.
The car is on a lift ~2' off the ground. No Wires hooked to the engine and the console / shifter is out for T-Tube removal next. Will raising the front or rear push more of the fuel to the pick up area? I don't know where that lives in the left tank. I just don't want to get a bath or start a fire when I put a Hole Saw to the tank. S#1T like this scares me a bit....
Seems like it was a success! Thanks for the guidance.
The car is on a lift ~2' off the ground. No Wires hooked to the engine and the console / shifter is out for T-Tube removal next. Will raising the front or rear push more of the fuel to the pick up area? I don't know where that lives in the left tank. I just don't want to get a bath or start a fire when I put a Hole Saw to the tank. S#1T like this scares me a bit....
Seems like it was a success! Thanks for the guidance.
