fuel pump issue
Thread Starter
Drifting
Joined: Aug 2011
Posts: 1,861
Likes: 1
From: panama panama
fuel pump issue
Today i when for a ride on the vette.
when i come back home and turn off the engine. I hear a noise from the back of the car. I find out the noise was coming from inside the fuel tank.
I think it was the fuel pump working even do the engine is off and the key on my packet.
so I disconect the car battery. and the noise stop. 2 minutes later i reconect the battery. and the noise come back.
so i disconect the battery again. . come back 2 hour later. reconect the battery. but this time. the noise was gone
Not sure if the noise is the fuel pump. but one think is for sure is coming out of the fuel pump.
Importand. I also disconect the fuel pump relay. and the noise continue.
I recoded the noice with my celphone. but i dont know how upload sound files.
please advice.
when i come back home and turn off the engine. I hear a noise from the back of the car. I find out the noise was coming from inside the fuel tank.
I think it was the fuel pump working even do the engine is off and the key on my packet.
so I disconect the car battery. and the noise stop. 2 minutes later i reconect the battery. and the noise come back.
so i disconect the battery again. . come back 2 hour later. reconect the battery. but this time. the noise was gone
Not sure if the noise is the fuel pump. but one think is for sure is coming out of the fuel pump.
Importand. I also disconect the fuel pump relay. and the noise continue.
I recoded the noice with my celphone. but i dont know how upload sound files.
please advice.
Last edited by hitmanpty; Jun 16, 2013 at 10:48 PM.
Safety Car
Joined: Aug 2002
Posts: 3,842
Likes: 230
From: SANTA CRUZ CA
From forum member jfb (a very knowledgeable member):
"Unplug the fuel pump relay and see if the fuel pump runs with the ign off. If it does then unplug the oil pressure switch and if the pump runs with ign off, you have a defective ECM, if not, then you have a defective oil pressure sw.
"There is no timer that keeps the fuel pump on after the ign is off.
The fuel pump gets power from the fuel pump relay which is turned on by the ECM and through the oil pressure switch which closes at 4 psi oil pressure. The ECM will not turn on the fuel pump relay when the ign is in off! So you should look at the oil pressure switch.
Next, unplug the fuel pump relay while the engine is running, then turn the engine off which proves the relay is the cause and if so, the ECM is suspect, assuming no other wires are screwed up keeping the ECM on with the ign sw off. The fuel pump relay could also be sticky and stay on for a short time after the ign is off and its coil is off. Unplugging it will tell you that."
Supporting link:http://forums.corvetteforum.com/c4-t...r-started.html
"Unplug the fuel pump relay and see if the fuel pump runs with the ign off. If it does then unplug the oil pressure switch and if the pump runs with ign off, you have a defective ECM, if not, then you have a defective oil pressure sw.
"There is no timer that keeps the fuel pump on after the ign is off.
The fuel pump gets power from the fuel pump relay which is turned on by the ECM and through the oil pressure switch which closes at 4 psi oil pressure. The ECM will not turn on the fuel pump relay when the ign is in off! So you should look at the oil pressure switch.
Next, unplug the fuel pump relay while the engine is running, then turn the engine off which proves the relay is the cause and if so, the ECM is suspect, assuming no other wires are screwed up keeping the ECM on with the ign sw off. The fuel pump relay could also be sticky and stay on for a short time after the ign is off and its coil is off. Unplugging it will tell you that."
Supporting link:http://forums.corvetteforum.com/c4-t...r-started.html
Last edited by don hall; Jun 16, 2013 at 11:12 PM.
Thread Starter
Drifting
Joined: Aug 2011
Posts: 1,861
Likes: 1
From: panama panama
I will check the oil swich tomorrow since is night all ready. the other thing is. that is not doing it any more. . I guest i will have to take a short ride again. hopping for the problema to come back
