I've been reading through the countless threads regarding catch can setups but I'm still confused. I originally wanted to run a line from the PCV to the can, can to the intake with a check valve and a small breather on the passenger side. My tuner said that wouldn't work with a MAF based tune. He wants me to delete the PCV all together. I'm concerned about running a breather setup because I don't want the truck to smell like oil (the wife already hates the smell from my catless exhaust). Could I run both valve covers to the can then run a line from the can to intake pre-turbo?

Can any of you help clear up how I should run the catch can/pcv? There is just so many different setups out there that I'm having trouble making sense of it all.

Thanks, everybody!

 

I run a pcv catch can that has a check valve to make it a vented setup under boost, closed loop pcv system under vacuum. It's made by mighty mouse solutions. Fit and finish is wonderful. I love mine. Works perfectly fine with my blended maf/ve tune on my 2010 sierra with turbo setup

 

Your tuner is wrong.
Check out CHODAs build.

Now depending on kit and power levels you can use Pcv or no Pcv.
No Pcv vent both valve covers.

 

I looked at this can on the web and have seen many positive reviews. How do you have the can hooked up?

 

Why would you treat the valve covers differently? Why would one be hooked up correct and the other just has a breather cap, which is the equivalent to just having an open fitting on the valve cover and calling it a day.

You want to PULL the blow-by out of the valve covers. A nipple on the intake pipe, as close as possible to the compressor inlet, will always have vacuum. Run a vacuum line from each valve cover to a sealed catch can, then a line from the catch can to the fitting on the intake pipe. That is all you need.

You don't want to run a breather cap for two reasons. 1, you have a maf and the air in the system is already metered [assuming draw through]. 2, as I said above you want to pull the blow-by out, and a breather cap on the valve cover will not achieve this.

 

This is how I was going to run it but when I told my tuner about it he said that having the can hooked to the intake before the turbo would pull too much vacuum on the intake manifold.

 

The vacuum from the intake would pull blow-by from the valve covers and only the valve covers. It has nothing to do with the intake manifold.

Consider another 'tuner'.