[zl1killer]

I've been around some time on cars in general and now new to Honda. Absolutely love my 2020 accord EX-L. I just got to digging on these forums and figuring out the PCV system to install a catch can on the car. I already installed the PRL intake on the car (at ~250 miles) and already noticed oil film on the inlet side to the turbo at the hard plastic inlet pipe. In looking up the mishimoto catch can, the installation instructions have you installing it at the back of the engine, intake manifold and valve cover connection, which they provide a check valve in their kit. PRE-installation of this check valve, when the car goes into boost doesn't this rear existing line leak air into the PCV system and at the front of the engine the turbo sucking on the PCV pulls the vacuum.

So here is what I'm getting at. Why from the factory is there a line at the intake manifold (boost pressure) that runs to the valve cover? Or did I miss something and there is more I don't see.
There definitely needs to be a catch can at the front of the engine at the intake connection as I can already see oil film albeit very little but it is there. Also knowing catch can kits currently install at rear it seems a multi point can with check valves properly installed may work and be able to use 1 can. Still thinking on this.

 

[Samuelx]

Maybe check with Mishimoto to see if they already looked into that?

 

[zl1killer]

I actually sent them an email prior to jumping on this forum and been looking at other catch cans and further looking at the car. I'm at the point now that I may connect some instrumentation that I have with some "T"s and spare tubing to see some baseline readings and then try setting up lines with the check valve and 3rd line to front valve cover connection.

 

[Samuelx]

Build that better mousetrap!

 

[Vegashybrid]

That line is part of the pcv system, it what's putting all that excess stuff back into the system to be burnt off. Hence positive crankcase ventilation or pcv. Also why don't need catch cans. Disconnecting that line could cause serious issues as well as codes. You could however to a vta or vent to atmosphere system and eliminate that from going into the valve cover but will be messy under engine bay. Look fo VTA catch can, or you could also install a check valve as you mentioned.