Sudden Fuel Pump Whine
Thread Starter
7th Gear
Joined: Feb 2019
Posts: 7
Likes: 0
From: ATX
Sudden Fuel Pump Whine
My C6 LS3 is taking us on a road trip through 3 states right now and after a long day of driving I noticed the fuel pump noticeably humming. In past GM vehicles I've had this and it was nothing, but my Vette was silent until today. Is this a red flag? I don't want to lose the pump in the middle of nowhere on a tight schedule.
32k miles on it. No codes or issues as of yet.
32k miles on it. No codes or issues as of yet.
Thread Starter
7th Gear
Joined: Feb 2019
Posts: 7
Likes: 0
From: ATX
Update:
Filled the tank from 1/2 and the fuel pump noise subsided. Drove from Santa Fe to Colorado and around there for 2 days with no issues. Drove from Colorado to Amarillo and the following morning the car wouldn't start. Cranked strong but wasn't catching. Swapped fuel pump relay for another one and it fired right up. Made it to just outside of Austin where I had to fill up and it died shortly after starting it at the gas station. Again, flipped around relays, and it fired up.
Now I'm home, the car is as hot as it can safely be, and it's idling a little lopey and makes me a little worried it'll die while idling eventually.
Drives great with no stuttering at any throttle position. I'm real confused. Searched and found 05s seemed to burn up relays from bad wiring in the harness. Would this be applicable to a 12? I've never had this issue until putting the car through the heat gauntlet of driving 30 hours round trip through TX/NM/CO.
Filled the tank from 1/2 and the fuel pump noise subsided. Drove from Santa Fe to Colorado and around there for 2 days with no issues. Drove from Colorado to Amarillo and the following morning the car wouldn't start. Cranked strong but wasn't catching. Swapped fuel pump relay for another one and it fired right up. Made it to just outside of Austin where I had to fill up and it died shortly after starting it at the gas station. Again, flipped around relays, and it fired up.
Now I'm home, the car is as hot as it can safely be, and it's idling a little lopey and makes me a little worried it'll die while idling eventually.
Drives great with no stuttering at any throttle position. I'm real confused. Searched and found 05s seemed to burn up relays from bad wiring in the harness. Would this be applicable to a 12? I've never had this issue until putting the car through the heat gauntlet of driving 30 hours round trip through TX/NM/CO.
Last edited by coalshark; Jul 14, 2019 at 05:22 PM.
Team Owner
Joined: Nov 2006
Posts: 21,136
Likes: 212
From: Long Island New York
Wouldn’t think a relay issue would make a pump whine and and a suddenly noisy pump making noise it hadn’t before is certainly a red flag and I would get it checked out by a competent mechanic and I would say it likely needs a new. My Mustang GT back in the day had similar fuel pump issues and twice needed to be replaced.
Thread Starter
7th Gear
Joined: Feb 2019
Posts: 7
Likes: 0
From: ATX
Drove around town today without issue, until on my way home I stopped to run an errand, got in the car and started it and it was running really rough...but didn't die. Popped the hood, swapped relays again and it fired up with no issues.
I cannot figure out why this fixes the problems. The relays aren't dead because where I'm swapping them into is unaffected and still functions. My best guess is by removing and replacing the relay I'm possibly fixing a bad connection in the terminals or resetting something.
I cannot figure out why this fixes the problems. The relays aren't dead because where I'm swapping them into is unaffected and still functions. My best guess is by removing and replacing the relay I'm possibly fixing a bad connection in the terminals or resetting something.
