Fuel Leak/Fuel Tank - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

ChatNoir82 · 11-22-2025, 02:28 PM

No accidents, modifications, or ever allowing a service mechanic to work on my Camaro. After smelling gas on the passenger side, I had a Chevy service department try to diagnose - "Something leaks, don't know what, and we won't touch it." Clear leak originating around the tank on passenger side but I cannot identify the source or failure mode. I extracted the tank (no cutting of sheet metal to create an "access door") and saw "wet" evidence around the primary fuel pump. I replaced O-ring seals on both primary and secondary pumps and reassembled everything and tested. Still leaking. Full tank extraction Number 2 and found no clear evidence of where leak is coming from. No broken/cracked piping, no failing fuel line connectors, no cracking of the top of either fuel pump, and no failing o-ring seal. Since extracting/reinstalling is a bear to do alone in my garage, I need to pressure test the tank/pumps/immediate fuel lines before reinstalling. I can't think of any other means to find/identify the leak. Anyone have any experience on this?

CamaroCracka · 11-30-2025, 06:33 AM

For me, the easiest way to pressure test would be to find another connector for the pump and supply voltage to it. These pumps are voltage modulated, but that occurs at the FPCM. If you put 12v to it, it will pump. Obviously, you will need to catch the fuel coming out and be in a well-ventilated area.

xstuntman · 11-30-2025, 09:43 AM

Just replaced my daughters fuel pump and found that the plastic pump housing itself was cracked which surprised me. I would've bet prior to pulling it was a hose, seal or connector.

With the tank out it would be a great time to fix GMs screw up and put in an access door.

ChatNoir82 · 12-02-2025, 02:10 PM

Thanks, CamaroCracka. You confirmed my thoughts. I took the tank to a mechanics shop and suggested pressure testing but they advised their tried n true 'smoke test' method. I was doubtful because only pressure or wind will move smoke. They came up with nothing. I'm going put two gallons in and to attempt to slide the tank under the Camaro enough to re-connect the pump power. I'll route a fuel line hose back into the filler pipe back into the tank and try to run it enough to spot the leak source. I suspect a crack in the fuel pump 'cap' or fuel line nipple - white plastic that might hide a crack. I'd hate to replace the fuel pump and still have a leak. It sure was easier doing such work on '89 Jeep Wrangler!

Thanks, too, Xstuntman.

CamaroCracka · 12-04-2025, 11:47 AM

Particularly with high pressure fuel pumps, what leaks at 60psi may not leak at 1psi.

11-22-2025, 02:28 PM	#1
ChatNoir82 Dave Drives: 2011 LT2 Join Date: Feb 2014 Location: Cape Coral, Florida Posts: 2 View My Garage	Fuel Leak/Fuel Tank No accidents, modifications, or ever allowing a service mechanic to work on my Camaro. After smelling gas on the passenger side, I had a Chevy service department try to diagnose - "Something leaks, don't know what, and we won't touch it." Clear leak originating around the tank on passenger side but I cannot identify the source or failure mode. I extracted the tank (no cutting of sheet metal to create an "access door") and saw "wet" evidence around the primary fuel pump. I replaced O-ring seals on both primary and secondary pumps and reassembled everything and tested. Still leaking. Full tank extraction Number 2 and found no clear evidence of where leak is coming from. No broken/cracked piping, no failing fuel line connectors, no cracking of the top of either fuel pump, and no failing o-ring seal. Since extracting/reinstalling is a bear to do alone in my garage, I need to pressure test the tank/pumps/immediate fuel lines before reinstalling. I can't think of any other means to find/identify the leak. Anyone have any experience on this? Attached Images

11-30-2025, 06:33 AM	#2
CamaroCracka Drives: 2010 Turbo LS3 Join Date: Dec 2009 Location: Palm Bay, FL Posts: 3,041	For me, the easiest way to pressure test would be to find another connector for the pump and supply voltage to it. These pumps are voltage modulated, but that occurs at the FPCM. If you put 12v to it, it will pump. Obviously, you will need to catch the fuel coming out and be in a well-ventilated area. __________________ 2010 SS - Kind of an On3 kit, CTR 78/80, CompCam 239/251 620/632 122+4, E85, Z28 suspension and ZL1 diff with Outlaw axles. Gen6 ZL1 brakes. 2011 Vert - 416/w 230/236 .612/.602 115lsa, 1LE suspension w/32mm rear bar. Z28 diff. Gen6 ZL1 brakes.

11-30-2025, 09:43 AM	#3
xstuntman Drives: 2012 Victory Red LFX Join Date: Dec 2012 Location: west central Texas Posts: 1,367	Just replaced my daughters fuel pump and found that the plastic pump housing itself was cracked which surprised me. I would've bet prior to pulling it was a hose, seal or connector. With the tank out it would be a great time to fix GMs screw up and put in an access door. __________________ '18 SS wheels, colored matched Heritage grille, actual driving lights, ZL1 strut tower brace, GM Performance billet aluminum fuel door, victory red rotors and calipers, 1/4 window American flags, splash guards, AEM dry panel air filter, Hot Wheels steering wheel and seat covers, Hot Wheels exterior emblems.

12-04-2025, 11:47 AM	#5
CamaroCracka Drives: 2010 Turbo LS3 Join Date: Dec 2009 Location: Palm Bay, FL Posts: 3,041	Particularly with high pressure fuel pumps, what leaks at 60psi may not leak at 1psi. __________________ 2010 SS - Kind of an On3 kit, CTR 78/80, CompCam 239/251 620/632 122+4, E85, Z28 suspension and ZL1 diff with Outlaw axles. Gen6 ZL1 brakes. 2011 Vert - 416/w 230/236 .612/.602 115lsa, 1LE suspension w/32mm rear bar. Z28 diff. Gen6 ZL1 brakes.

12-02-2025, 02:10 PM	#4
ChatNoir82 Dave Drives: 2011 LT2 Join Date: Feb 2014 Location: Cape Coral, Florida Posts: 2 View My Garage	Thanks, CamaroCracka. You confirmed my thoughts. I took the tank to a mechanics shop and suggested pressure testing but they advised their tried n true 'smoke test' method. I was doubtful because only pressure or wind will move smoke. They came up with nothing. I'm going put two gallons in and to attempt to slide the tank under the Camaro enough to re-connect the pump power. I'll route a fuel line hose back into the filler pipe back into the tank and try to run it enough to spot the leak source. I suspect a crack in the fuel pump 'cap' or fuel line nipple - white plastic that might hide a crack. I'd hate to replace the fuel pump and still have a leak. It sure was easier doing such work on '89 Jeep Wrangler! Thanks, too, Xstuntman.