1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

New rebuild - Fuel Problems

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Old Jan 23, 2011 | 06:51 PM
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From: KC
New rebuild - Fuel Problems

I have recently rebuilt the 12A in my 1985 GSL and the car is having fuel issues. The car has set for 10 years so I drained the tank and replaced and fuel filter. The issue is that the engine will not run without pouring gas down the carb and will die once that fuel is used. I tested the flow of gas to the carb and I have none. I pulled the connector from the fuel pump and cranked and looked for 12 volts and did not see and voltage and the car side of the fuel pump connector. I then ran a wire from the positive side of the battery to the fuel pump and did not hear the pump come on.

Is running a 12 volt source straight to the pump a valid test? I know I should check the fuel supply line to the carb with air but haven't done that yet. I'm thinking I should just replace the pump but they seem to be pricey at about $140 at RockAuto and O'Reilly Auto but wil get one if it's needed. Also, is there an easy test for the fuel pump relay under the dash?
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Old Jan 23, 2011 | 08:19 PM
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From: Orlando/Winter Park
Check your ground.... Just getting power is not enough if the circuit is not complete
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Old Jan 23, 2011 | 09:13 PM
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From: KC
Originally Posted by 81WideMariah
Check your ground.... Just getting power is not enough if the circuit is not complete
I grounded it through the connector. I took a spare connector and put the grounded side to the body and the other straight to the battery. I left to pump in place and checked to see if it made a noise and had flow. No luck.
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Old Jan 24, 2011 | 11:45 AM
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try Atkinsrotary for pump
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Old Jan 24, 2011 | 12:04 PM
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From: KC
Originally Posted by keithscuba
try Atkinsrotary for pump
Darn. I just bought one from Advance Auto for $108 shipped earlier today. I got $40 off and free shipping. Atkins has a better price. I just checked them out and they have a really good price for fuel pumps.

SKU N249-13-400B
Weight 3.00 lbs
Price: $98.50
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Old Jan 24, 2011 | 12:14 PM
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Swings and Roundabouts ! Atkins is stock pump but there's also an Airtex E8124 around but more pricey .
I just ordered the Atkins and shipping to UK is horrendous $50. USPS
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Old Jan 24, 2011 | 01:30 PM
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From: KC
Originally Posted by keithscuba
Swings and Roundabouts ! Atkins is stock pump but there's also an Airtex E8124 around but more pricey .
I just ordered the Atkins and shipping to UK is horrendous $50. USPS
The Airtex E8124 is the one I ordered. I'm sure it will work fine.
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Old Jan 30, 2011 | 09:39 PM
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From: KC
I made some progress in troubleshooting my fuel issues. here is what I know.

We tested the fuel pump again by jumping pins BW and LW on the fuel pump relay connector B-06. The pump came on and we have fuel at the input of the carb. Flow was great. We next tested the fuel pump relay by taking it out of the car and putting 12 volts on connector BW and a ground on BY. The relay activated and we had continuity on the switch side of the relay. This would indicate that the relay was good. I also tried another fuel pump relay from another car. Neither relay would make the pump run when the ignition was cranking. I also check for 12 volts ate the fuel pump connector when cranking the car and did not measure 12 volts.

Is there something I'm missing? The car will start with a jumper in place of the relay. But will not start with any replay I tried.

I noticed that the fuel pump replay is connected to the Emission Control Unit. Does the replay send a voltage to the unit or is the relay getting a ground from the unit?
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Old Jan 30, 2011 | 11:42 PM
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From: Jax, FL.
I think i read on here, (Rx7 doctor maybe) that the fuel cut relay needs the emission unit connected(and working I guess) in order for it work.
I don't know what the signal is.
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