Fuel pump issues?

Reply Subscribe

Thread Tools

Search this Thread

Mar 20, 2008 | 10:50 PM

CorvetteMike2024

Thread Starter

Corvette Enthusiast

Joined: Oct 2007

Posts: 6,791

Likes: 2,697

From: So. Cal.

2025 C7 of the Year Finalist- Unmodified

2024 C7 of the Year Finalist - Unmodified

2023 C7 of the Year Finalist - Unmodified

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.

Mar 20, 2008 | 11:29 PM

StephensblackL98

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.

Mar 20, 2008 | 11:31 PM

rodj

Le Mans Master

Joined: Aug 2000

Posts: 8,838

Likes: 31

From: Australia

Quote:

Originally Posted by CorvetteMike2004

. When I turn on the key, no pump sound. Cranks about 10 seconds before catching. Once started, runs perfect.

Fuel pump relay /connector plug or wiring to it / no signal from computer.

"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

Mar 21, 2008 | 11:11 PM

CorvetteMike2024

Thread Starter

Corvette Enthusiast

Joined: Oct 2007

Posts: 6,791

Likes: 2,697

From: So. Cal.

2025 C7 of the Year Finalist- Unmodified

2024 C7 of the Year Finalist - Unmodified

2023 C7 of the Year Finalist - Unmodified

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?

Mar 22, 2008 | 12:23 AM

RRT vette

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.

Mar 22, 2008 | 01:16 PM

CorvetteMike2024

Thread Starter

Corvette Enthusiast

Joined: Oct 2007

Posts: 6,791

Likes: 2,697

From: So. Cal.

2025 C7 of the Year Finalist- Unmodified

2024 C7 of the Year Finalist - Unmodified

2023 C7 of the Year Finalist - Unmodified

new relay

I put in the new relay, still no pump sound. Any more suggestions? Thanks again

Mar 22, 2008 | 02:26 PM

CFI-EFI

Race Director

Joined: Sep 2000

Posts: 17,298

Likes: 33

From: The Top of Utah

Throw more money at it.

RACE ON!!!

Mar 22, 2008 | 02:49 PM

rick lambert

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.