P0446 code persistent problem

[jigsaw]

Hello all,
I am new to this forum and would like some help with my 2000 Sierra 5.3 ext. cab. I love this truck but I have a P0446 code and after extensively researching it I ended up replacing the purge valve and the evap vent valve because they were both inexpensive and not too hard to reach. This did not fix the problem and so I took it to my local auto repair place and they told me that my fuel level sensor circuit was tested and on the low side, they said that I will need my fuel pump replaced and it will fix the code P0446. has anyone ever heard of this? I have yet to find any info about an evap system fault that gets fixed by replacing a faulty fuel level sensor. Unfortunately it is all contained in the fuel pump so that is their logic, replace it and fix the code. Any ideas? Thanks for any advice.

 

[98trck]

have you replaced the gas cap
with the evap code you have a leak in the system
usually the gas cap is at fault but you may have a cracked rubber vent line
I have in the past taken an old gas cap and put a wheel valve stem in it and pressurized the gas tank and listen and found the bad rubber line

 

[jigsaw]

Hey there,
Yes, I recently changed the gas cap because it was not clicking after 2 turns. Turns out it was cracked. Still get the code and I am more confused now then ever.

 

[Liquorice]

I've been getting that code off and on for a couple of years now. I've been ignoring it as I don't consider it too much of a concern.
Replaced my fuel pump last winter (it failed) and I'm still getting the evap code.
So I don't think the fuel level gauge is necessarily the answer.
2002 / 4.8 / extended cab.

Sam

 

[H/H Specialist]

Check ground wires from the hood that connect into the back of the engine firewall.... Mine were broke and I kept getting that code... Fixed ground wire... Codes went away... A repair shop told me the same thing about the fuel pump ...