Hi Everyone,

This is my first time posting, so hope I'm in the right place to ask this question.

I own a 2006 Silverado 1500 (5.3L 4x4) that is throwing the EVAP code. At this point I have replaced the gas cap, the charcoal canister (I don't know the technical name), and the purge and vent solenoid. I also noticed that the vent solenoid hose going to the charcoal canister was cracked so I thought that was the issue, so I resolved it by using a radiator hose and hose clamps to replace the OEM hose. After doing all of that, I figured out that the vent solenoid is not getting a ground. The other lead has power, but none on ground. I was looking at a schematic recently and it showed ground is obtained from the computer. I have checked as much as I could and did not see a broken or loose wire that is not allowing the circuit to complete.

Has anyone had this issue or have any suggestions? I read somewhere that you should not ground to the frame because it could cause issues with the computer but don't know specifics. Any help is appreciated.

 

Exactly which EVAP DTC is being thrown? There are several different EVAP related DTCs.

 

mine has had a check engine light for evap for a year or more now, I replaced the normal things that it usually is but after I performed a smoke test and with a one of those long boroscope type cameras I was after to feed it up on top of the gas tank and see that the gasket for the fuel pump has failed and smoke was coming out of inbetween fuel pump and gas tank

 

Sounds like you found it.

One cannot guess the cause of a check engine light. One must use a decent OBDII code reader/live data scanner or else you'll be throwing darts in the dark.

 

Sorry about the delayed response. The codes are P0446 (Evaporative Emission System Vent Control Circuit) and P0446 (Evaporation Emission System Vent Control Circuit). I replaced the pressure sensor on the fuel tank and then cleared the code. I've started/stopped the truck around 10 times and drove about 100 miles since changing it this weekend, and so far, so good. I hope that resolves the issue.

 

Hello, I did check it with a code reader, I responded below with the codes. Sorry for the delayed response.

 

I smoke tested but all the smoke was coming out of the vent solenoid since it wasn't closing when the truck fired up. I ended up changing the fuel tank pressure sensor and I think that may have been the solution in this case. I did that after reading a Haynes manual I recently purchased and received from Ebay. The manual states that once the truck fires up a series of events (engine temp, pressure in evap system, etc) must be met before the computer closes the vent solenoid.

 

If those two codes return, you need to check the wiring to the EVAP system Vent Valve. Remember there are 2 valves/solenoids - An EVAP Vent Valve and an EVAP Purge Valve.