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Low voltage at fuel pump

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Old 06-11-2012, 08:54 PM
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Default Low voltage at fuel pump

I have a 95 S10, Vortec v6,4.3,4door, 4 wheel drive. It has low fuel pressure. With a brand new Bosch pump in. So I ck voltage at pump. Its only 8.6 volts. Everywhere else I ck I get 12. What am I missing????
 
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Old 06-11-2012, 10:14 PM
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Just a friendly FYI: aftermarket fuel pumps are NOT recommended on 4.3L Vortec engines, AC Delco or Delphi only, unless you like changing the pump

When the ignition is turned to the RUN position, (engine off) the fuel pump is only energized for 2 seconds, so you must check voltage during that 2 second time frame. Have you checked resistance from the fuel pump module electrical connector to ground? Must be less than 5 ohms. Which style connector is on the pump module?



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Old 06-12-2012, 07:06 PM
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Originally Posted by Captain Hook
Just a friendly FYI: aftermarket fuel pumps are NOT recommended on 4.3L Vortec engines, AC Delco or Delphi only, unless you like changing the pump

When the ignition is turned to the RUN position, (engine off) the fuel pump is only energized for 2 seconds, so you must check voltage during that 2 second time frame. Have you checked resistance from the fuel pump module electrical connector to ground? Must be less than 5 ohms. Which style connector is on the pump mo

My connector is only a 3 wire. At key turn on I do get the 12+ v. But resistance is around 30.
 
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Old 06-12-2012, 07:33 PM
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My bad, 1995, sorry. 30 ohms is too much resistance in the ground circuit, (probably what toasted the old pump). Solder on a 14 gauge piece of wire at the module connector and run it to a good, clean, body ground.
 
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Old 06-13-2012, 10:03 PM
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Originally Posted by Captain Hook
My bad, 1995, sorry. 30 ohms is too much resistance in the ground circuit, (probably what toasted the old pump). Solder on a 14 gauge piece of wire at the module connector and run it to a good, clean, body ground.
Capt. Hook. Thank you very much. Did that tonite. 1ohm. Hopfully this all works out. Darn tired of droppin that tank.
 
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