Fuel pump issues?
Thread Starter
Corvette Enthusiast
Joined: Oct 2007
Posts: 6,795
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From: So. Cal.
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Fuel pump issues?
89 vert. When I turn on the key, no pump sound. Cranks about 10 seconds before catching. Once started, runs perfect. Any issues here? Shouldnt I here pump in the on position before cranking? Thanks all for input. 
Burning Brakes
Joined: Jan 2001
Posts: 959
Likes: 1
From: Plano, Texas
Perhaps I'm just hard of hearing, but I've owned four C4's, and I've not heard the fuel pump, yet.
If it takes 10 seconds for the motor to fire, something ain't right. Anything from coil to plugs to injectors, to about a dozen other things. I'm sorry, I'm not helping a lot. I've had L98's like yours, and LT1's. Never took 10 seconds to start. Good luck finding your problem.
However, if you find you have to replace the fuel pump, it's a breeze. I have just completed the job, and it's the easiest thing you'll do on your car.
If it takes 10 seconds for the motor to fire, something ain't right. Anything from coil to plugs to injectors, to about a dozen other things. I'm sorry, I'm not helping a lot. I've had L98's like yours, and LT1's. Never took 10 seconds to start. Good luck finding your problem.
However, if you find you have to replace the fuel pump, it's a breeze. I have just completed the job, and it's the easiest thing you'll do on your car.
Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
"Cranks about 10 seconds before catching."
You are starting on the fuel pump oil pressure switch which runs pump after oil pressure builds.
Check pump relay first.
Can swap with the fan relay to confim operation
Thread Starter
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From: So. Cal.
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relay
Which relay is for fuel pump? I have one by wiper motor and one on fender well. Thanks for help. Are these it? If not where?
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
The fuel pump relay is located on the firewall next to the windshield wiper motor. You can get a fused jumper wire and stick one end into the first terminal on the fuel pump relay connector and the other end into the last terminal of the fuel pump relay connector. This will bypass the relay and the fuel pump should run (key off), if this is your problem.
Thread Starter
Corvette Enthusiast
Joined: Oct 2007
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From: So. Cal.
2025 C7 of the Year Finalist- Unmodified
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new relay
I put in the new relay, still no pump sound. Any more suggestions? Thanks again
Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
I'd check the wiring going into the fuel pump relay, several of us have found the insulation on these wires shrink back and expose bares wires. Mine had shrunk 3/4 of an inch and were in contact with one another. If you run a wire from the positive side of the battery to terminal G on the ALDL, the only pin on the lower side your fuel pump should come on...if it does you have a wiring circuit problem. And you might want to just swap the relay with the one on the wheel well...just to make sure even the new one is good. The ALDL is just above your knee on the drivers side.
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