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Fuel Pump stays running (No 12V mod)

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Old 09-17-12, 07:19 PM
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SC300_704
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Default Fuel Pump stays running (No 12V mod)

ok so i recently notice my fuel pump stays running when i turn the key on to the on position. i have tried the 12V mod before but didn't like it due to the fuel pump stays running all the time so i switched back to stock. everything was normal for over a year, the 2 wires that i stripped was soldered and shrink wrap so no loose connection there. sometimes when i start the car i can hear the fuel pump going from loud to quiet and vice versa and that's only on idle. can the fuel pump ecu be bad or maybe something else?
Old 09-17-12, 07:44 PM
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HiPSI
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Maybe try checking the volts at the fuel pump and see if it's fluctuating at idle.
Old 09-18-12, 04:17 PM
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talked w/ a buddy on mines and he thinks the fuel pump relay might be stuck open and giving the fuel pump constant power..is there a way to test the relay out to see if it's still good or not?
Old 09-20-12, 02:48 PM
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well i tried switching relays and it still does the same thing. but i do notice sometimes if i turn the key to on, about 10 sec later the fuel pump will kick in and start running. and last but not least i don't know why sometimes when i close (have to slam it to lock) the hood while the car is running, the car will just die for no reason....??

Last edited by SC300_704; 09-20-12 at 02:57 PM.
Old 09-20-12, 02:59 PM
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oh yeah almost forgot, i unplugged the iacv while the car is running and there's no sudden changes on idle. why is that? btw just installed a new/used iacv a couple of days ago to.
Old 09-21-12, 07:08 PM
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the fuel pump staying on would tell me the fuel ecu is bad. i would redo the 12v mod (you could put a relay in so its safe).
Old 11-12-12, 06:51 PM
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just an update, i replaced the fuel pump ecu and also swap my ecu w/ a spare and still same thing. now i'm thinking it's the fuel pump itself maybe?
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