What's a fuel pump relay???
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Joined: Dec 2000
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From: Farmington NY
What's a fuel pump relay???
I periodically will get a check engine light on a warm restart and then a rough idle. The code will be either low voltage or high voltage to the fuel pump relay??? What is this, it is very intermittant. I had a new serpentine belt put in last year (ever since it has a slight rattle to one of the pulleys. What's up???
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Joined: Dec 2000
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From: SE NY
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Re: What's a fuel pump relay??? (Gregory VanLare)
For two seconds after you turn the ignition key on the ECM energizes the FP relay to prime the fuel rail.
Thereafter power to the FP is supplied only through the oil pressure sw (located behind the intake base to the left of the dist).
There is a feebback line from the FP power line into the ECM.
If the code it tossed only at start up check the fuel pump relay; if during engine operation the oil pressure sw may be intermittently dropping out causing that code.
To find the pulley that's ratteling you may be able to see it or put (carefully) a rubber tube on each device to isolate the source.
[Modified by 65Z01, 5:31 PM 10/12/2002]
Thereafter power to the FP is supplied only through the oil pressure sw (located behind the intake base to the left of the dist).
There is a feebback line from the FP power line into the ECM.
If the code it tossed only at start up check the fuel pump relay; if during engine operation the oil pressure sw may be intermittently dropping out causing that code.
To find the pulley that's ratteling you may be able to see it or put (carefully) a rubber tube on each device to isolate the source.
[Modified by 65Z01, 5:31 PM 10/12/2002]
