fuel pump?
Thread Starter
Melting Slicks
Joined: Sep 2001
Posts: 3,094
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From: Dover De
fuel pump?
Not pumping. Changed the relay still not working. Checked the fuel rail and no pressure. I hear no fuel pump when the key is turned on. This is on an 88 and i have no clue how to check it out any ideas? :crazy:
Race Director
Joined: Oct 2001
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From: Fear causes hesitaiton...and hesitation will cause your worst fears to come true. Houston TX
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Cruise-In VII Veteran
Re: fuel pump? (emsrescu)
Has anyone else ever noticed, that when it is time to do a fuel pump replace job, the tank is ALWAYS full. :rolleyes:
Safety Car
Joined: Feb 1999
Posts: 3,504
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From: Mexico Beach FL
Re: fuel pump? (emsrescu)
If I remember correctly (I don't have my schematics at work) this is how it works:
When you turn the key on, power is supplied to the fuel pump through the fuse. Then, the ECM supplies to ground to the fuel pump to complete the circuit and the pump should run for two seconds. If the oil pressure builds up to 4 psi to close the switch to keep the pump running during that two seconds, the pump will keep running. If it the oil pressure does not build, the pump will quit.
The easiest way to check the pump would be to make sure the fuel pump fuse is ok and ground the negative side of the pump to see if it runs. If the pump runs this way, the pump is OK and the problem is in your oil pressure switch, ECM or wiring.
I don't know what year it started, but the security system can stop the pump from running -- I think GM calls it FEDS (Fuel Enable ???? System).
Tom Piper
[Modified by Tom Piper, 8:28 AM 2/5/2002]
When you turn the key on, power is supplied to the fuel pump through the fuse. Then, the ECM supplies to ground to the fuel pump to complete the circuit and the pump should run for two seconds. If the oil pressure builds up to 4 psi to close the switch to keep the pump running during that two seconds, the pump will keep running. If it the oil pressure does not build, the pump will quit.
The easiest way to check the pump would be to make sure the fuel pump fuse is ok and ground the negative side of the pump to see if it runs. If the pump runs this way, the pump is OK and the problem is in your oil pressure switch, ECM or wiring.
I don't know what year it started, but the security system can stop the pump from running -- I think GM calls it FEDS (Fuel Enable ???? System).
Tom Piper
[Modified by Tom Piper, 8:28 AM 2/5/2002]
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From: The Top of Utah
Re: fuel pump? (Rob 91Z07)
Has anyone else ever noticed, that when it is time to do a fuel pump replace job, the tank is ALWAYS full. :rolleyes:
The Corvette is one of the few cars where you don't have to deal with the gasoline to change an in tank pump. Besides, the less air in the tank, the less volitile air/fuel mixture to explode. There's nothing more dangerous than an "empty" gas tank.
