NEED HELP P0455 EVAP System Performance Problem

[dieselscrub]

Hi, guys, I have 04 Chevy TrailBlazer 4.2 L6 and it has a large gross leak, I bought a new gas cap, Purge Valve, and Vapor Canister Vent Valve.
Does anyone have pictures or a diagram where to locate these so I can replace them? I'm just going to start on these I might have to change out a few other parts as well. Has anyone done this before and know what to do? I seen on youtube they used a smoke machine to find where the leak is but I don't have a smoke machine, This is my little project I'm working on, hope to hear something soon thanks, guys.

 

[Mooseman]

Do you know somebody who vapes? There's your smoke machine.

 

[xavierny25]

Purge valve is on the driver side of the engine block close to the starter. The canister is under the truck by the gas tank just depends how you are looking up at it, its above the rear diff you cant miss it.

 

[Pygot]

Hi, guys, I have 04 Chevy TrailBlazer 4.2 L6 and it has a large gross leak, I bought a new gas cap, Purge Valve, and Vapor Canister Vent Valve.
Does anyone have pictures or a diagram where to locate these so I can replace them? I'm just going to start on these I might have to change out a few other parts as well. Has anyone done this before and know what to do? I seen on youtube they used a smoke machine to find where the leak is but I don't have a smoke machine, This is my little project I'm working on, hope to hear something soon thanks, guys.

I have this exact problem on my saab 08 97x 4.2L which is the same setup to my knowledge

 

[Brian K]

The rear one is moderately easy to change, the one in the engine bay a little trickier. An extra set of elbows would sure have helped. I changed both purge valves last spring after getting the codes with replacements from Rock Auto. After a few months, I'm occasionally getting the codes again. You could take the valves out and test them with 12 VDC to see if they actuate, but they are pretty cheap and removal is kind of a PITA so I thought I may as well change both rather than just one. I tested the old ones afterwards and one wasn't clicking and I couldn't blow through it.