painter306

I run mine down to about an eighth left, but when i fill i cuts off at 15.195 gallons every time any station. Its an 01 vert, i use bp, quick trip, or mobile....shell sometimes no chevron by me. Ive only had the gauge show full once even after multiple techron treatments, it used to read 15/16 now reads 7/8 after fill up. Ive even let the car sit for a few to let the tanks even out but rarely get over 16 gallons in. After reading this i think my gauge's calibration may be off. Could the second sending unit cause this problem? The gauge goes to 0 after 50 minutes of run time but when i clear the code it goes back to being accurate.

I didnt see anyone mention this but i usually get between 290 and 320 miles per fillup depending on my moods that week and the amount of highway i drive

Jistari

Two things come to mind, 1) the fuel pump is immersed in fuel, which keeps it cool and extends the life and 2) the corrosion problem with the swept area on the sending units may be exacerbated by the wet/dry/wet/dry situation encountered when fuel level is low.

I cant reference or prove number two, but the problem is related to deposits forming on the sensor and logically that would be accelerated in the condition stated above.

Just a note that letting the fuel level go very low very often may not be beneficial to the system.

Fuel system design in following posts.

http://forums.corvetteforum.com/c5-g...uestion-2.html

http://forums.corvetteforum.com/c5-g...l-problem.html

Totally understand the motive, fuel prices are out of control, just passing the info along.

f6john

+1 I can't speak specifically to the C5 but many earlier GM cars were subject to fuel pump failures due to operating the cars with very low fuel levels. I try to never let the fuel level fall below 1/4 tank for that reason especially since we have the pump that moves fuel from one tank to the other.

DeeGee

I'll confuse the issue

02 Fuel System Description
Two fuel tanks containing 9 gals each store the fuel supply. An electric fuel pump attaches to the fuel sender assembly inside the left fuel tank. The fuel pump pumps fuel through the fuel feed pipe (6) and an in-line fuel filter (9) to the fuel rail. The rear fuel feed pipe (6) has an integral check valve (4) in order to maintain the fuel system pressure in the feed pipe. The pump provides the fuel at a pressure greater than what is needed by the fuel injectors. The fuel pressure regulator, part of the fuel filter (9), keeps the fuel available to the injectors at a regulated pressure. A fuel return pipe (7) returns the unused fuel to the left fuel tank. The fuel pump also feeds the fuel through a tee (5) with an orifice in the fuel feed rear pipe (6) and through the auxiliary fuel feed rear pipe (2) in order to supply the siphon jet pump inside the right fuel tank. The siphon jet pump transfers the fuel from the right fuel tank to the left fuel tank through the auxiliary fuel return rear pipe (3, 8).:





(1)Fuel Feed Pipe (2)Auxiliary Fuel Feed Rear Pipe (left tank to jet pump) (3)Auxiliary Fuel Return Rear Pipe (jet pump to left tank) (4)Fuel Feed Pipe Check Valve (5)Fuel Feed Pipe Tee with Orifice (6)Fuel Feed Rear Pipe (to fuel filter/fuel pressure regulator and siphon jet pump) (7)Fuel Return Rear Pipe (8)Auxiliary Fuel Return Rear Pipe (jet pump to left tank) (9)Fuel Filter/Fuel Pressure Regulator

Jistari

Damn it

Reading FTW :bb

smitty2919

I know this is a old thread bump, I don't care. This info was exactly what I was needing and looking for! Tons of info on new fuel systems but not much on old style!
Thank You!

Dodgeturbpo

Ha Ha mine usually drops to zero even with a full tank 😡