Mystery Hose - 3.4L 5VZ-FE Tundra 2003

Hello to all and a huge thank you in advance to anyone who can help me out identifying a hose that needs to be replaced.

Truck has been throwing the P0442 small evap leak code lately and after further inspection looks like I have a hose failing right at the lower connection point.

Searched far and wide looking for evap / vacuum / vent hose diagrams and this one is often left unlabeled. Assuming some sort of breather or intake hose. The one I’m running now (in photos) is a mostly insulated line that runs directly behind the valve cover.

Just trying to find a part number or the name of this hose. Really appreciate any info. Thanks.

 

I looked up a random-ass RCLB with your same specs and plugged it into the EPC.

Here is the vacuum/hoses section. Does it help? https://toyota-usa.epc-data.com/tundra/vck30/3828/engine/1708/?full

I have far less familiarity with the 5VZ-FE, so I think your eyes may be better suited than mine to find the right tube. Click on any number on there to get the part name/number.

Note: The canister at the bottom of that image is the EVAP canister which typically contains charcoal and a purge/vent valve in most cars. Hoses attached backwards on that, or cracked on the ends (which is common after 10+ years) can cause leak codes. But if you clearly see something disco'd, let's identify what it is and go from there. I bet the FSM (service manual) will cover it, it's linked in the community megathread sticky.

 

If I'm remembering correctly, that is a vapor exhaust hose from the drivers side valve cover to the intake. The purpose is to suck excess gasses from the VC and recirculate them back into the intake of the engine.

I might be wrong, it's been a long time since I've had anything to do with the 5VZ-FE

Replacing it with any hose strong enough to withstand the atmospheric pressures imparted on the hose caused by the vacuum of the intake, as well as the oily vapor of the valve cover should be fine to do.

 

Thanks for the help guys, Tundra2 I’m pretty sure you nailed it, the low side of the hose is connected to what looks like the back of the valve cover / crank case, too high to be reaching the evap canister. That would explain the evap code and a slight taptaptaptap noise coming from air escaping through that crack in the hose when I’m idling. Looks like an easy replacement, knowing all this I can probably find the part number easier, if not, fabricate one. I’ll post a follow up. Thanks again.

 

Bingo

https://www.partsgeek.com/q9qls8l-t...AAAAD_bfN7zRVlSas_eAJdOQKuzB12iH#immersedview