1984 Fuel Pump problem
Thread Starter
1st Gear
Joined: Jan 2015
Posts: 1
Likes: 0
1984 Fuel Pump problem
I have recently bought a 1984 corvette. The problem I am having is the fuel pump wont shut off. I have to disconnect battery to get it to shut off. I have disconnected the fuel pump relay and I have also open up the gas tank and disconnected the fuel pump connection there. It still runs!. I have heard that depending on year some draw power from different points. Is it possible the power is coming off the starter?
Has anyone else had this problem?
I have tested the fuel pump and it is working and making contact it just seems like it is a wiring problem.
Any information on this would be greatly appreciated.
Thanks,
Scott
Has anyone else had this problem?
I have tested the fuel pump and it is working and making contact it just seems like it is a wiring problem.
Any information on this would be greatly appreciated.
Thanks,
Scott
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
Look at the oil pressure switch on the back of the engine block behind the distributor. The wires for the fuel pump are orange and red.
3rd Gear
Joined: Nov 2014
Posts: 3
Likes: 0
From: Centerville Ohio
Same thing
I have recently bought a 1984 corvette. The problem I am having is the fuel pump wont shut off. I have to disconnect battery to get it to shut off. I have disconnected the fuel pump relay and I have also open up the gas tank and disconnected the fuel pump connection there. It still runs!. I have heard that depending on year some draw power from different points. Is it possible the power is coming off the starter?
Has anyone else had this problem?
I have tested the fuel pump and it is working and making contact it just seems like it is a wiring problem.
Any information on this would be greatly appreciated.
Thanks,
Scott
Has anyone else had this problem?
I have tested the fuel pump and it is working and making contact it just seems like it is a wiring problem.
Any information on this would be greatly appreciated.
Thanks,
Scott
Did changing the oil pressure switch fix yours?
Last edited by jsatterf; Jan 19, 2015 at 10:45 AM.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
Remember that the fuel pump relay and the oil pressure switch are in parallel. That means that if either of them gets stuck in the "on" position then your fuel pump will run all the time. Find out which one by unplugging...
Heel & Toe
Joined: Jan 2015
Posts: 24
Likes: 0
From: Caldwell
Ok
Im fairly new to the forum, but recently had my pump out of my 84. You say you unplugged the conector at the tank and it still ran??? There are three wires on that connector. A ground, the ground to the fuel guage, and the power to the pump. If you disconected that connector there isnt any way the pump can run or recieve power. Are you sure you are hearing the pump?
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
This is what I have (1986):
Later years have this:
3rd Gear
Joined: Nov 2014
Posts: 3
Likes: 0
From: Centerville Ohio
When I realized it was the fuel pump running, I disconnected the battery and was looking at what all was involved. Hooked the battery back up, no issue. Engine fired right up and ran fine, some type of winter gremlin?? Haven't heard the pump run (with key off) since. Looks like I will add some items to my winter project list.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
Melting Slicks
Joined: Jan 2008
Posts: 2,054
Likes: 120
From: AZ
I once found a sticking relay, due to erosion of a contact surface. It had formed a hook-shaped surface that caused an intermittent ON problem, caused by arcing as the contact closed. The better relays have a capacitor that prevents that spark.
A few strokes with a small file fixed it; then a new relay.
A few strokes with a small file fixed it; then a new relay.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
Cliff, the set-up you have looks like what is on my 85, which of those components is the switch and which the sender? The switch is the one controlling the fuel pump correct?
When I realized it was the fuel pump running, I disconnected the battery and was looking at what all was involved. Hooked the battery back up, no issue. Engine fired right up and ran fine, some type of winter gremlin?? Haven't heard the pump run (with key off) since. Looks like I will add some items to my winter project list.
When I realized it was the fuel pump running, I disconnected the battery and was looking at what all was involved. Hooked the battery back up, no issue. Engine fired right up and ran fine, some type of winter gremlin?? Haven't heard the pump run (with key off) since. Looks like I will add some items to my winter project list.