Do I have to use PCV with breather?

[str8stang036]

I think i read once that if the PCV was in and there was a breather that, that would make it a vaccum leak. I just wanted to make sure if I fine using the PCV and the breather or no PCV and yes breather?

 

[final5-0]

I'm not sure on this but I have seen many say that using a breather allows unmetered air and this messes with
the pcm's ability to keep a/f ratio like it needs to be in closed loop.

Later
Grady

 

[yellow1995Cobra]

str8stang - Im not sure the reason ur using the breather.. Im guessing the VC's ur using have no oil fill neck?

I had to cut my oil fill neck off and this is what i did - i got a rubber gromet and stuck it in the hole in the VC, the inside diameter of the gromet is the same as a pcv valve.. So i just cut the inside of the pcv valve out (not sure if its necessary) and stuck it in the gromet. Then used a short piece of vacuum hose to conect the pcv valve to the normal stock location on the inlet pipe.

Before i did this i just ran a breather and had no problems, so who knows.

 

[str8stang036]

yeah the covers im installing dont have a filler neck. I was just wondering if I would be ok.

 

[S/CBlack95GT]

I run a breather with the PCV in place and it works great. It does allow unmetered air but it doesn't seem to cause any problems. My idle increased by 50-100rpms, but that was it.

 

[str8stang036]

Thanks guys