I used to run it with a breather.. car ran fine but I had split fuel trims.. I put the hose on with a Deutsch breather and no more split feul trims.. does it matter how i run this? is it going to make a performance difference? I doubt it but im just wondering..

 

I have heard that it doesn't. I have run a breather on my trans am since I had my intake manifold gasket replaced due to an oil leak. I figured that this would relieve some of the pressure and I haven't leaked a drop since.

If there are consequences of running a breather I would be interested to learn them as well.

 

well i did two data master logs.. One with a breather that i have run since my cam and head install.. one with the Deutsch BF412 breather hooked up to the valve cover/TB.. I had split fuel trims (BLMs) with the breather... (which is the computer correcting for the unmetered air gettting in the motor).. and the BLMs were perfect when i had the valve cover/TB hooked up with the deutsch breather.. http://collop.cz28.com/custom2.html

 

but since the computer is correcting it is there a problem with performance?

 

A valve cover breather is fine, you must have not had the tb plugged up good enough(vaccum capped) cause if you run a valve cover breath, there no way the computer can sense un metered air coming in threw the cover. it should only pick up un metered air in the intake stream( intake mainfold leak, tb not sealed etc).

 

The comp still senses the extra air.. and yes i had the TB capped off..

 

How?

 

I Dunno.. you got me.. Thats what i was told. Maybe it see the extra air through the O2 sensors? I was showing a High lean condition.. on the LT trims on data master. Now its fine.. explain that.. lol

EDIT:: i think its because the manifold pressure was getting lost since the breather was on there and not the closed PCV system which balances out everything.. thats why i was seeing split blms

 

any air that got in threw the breather would never see the inside of the combustion camber, so your o2s cant pick it up.

 

http://web.camaross.com/forums/showt...pcv+combustion

 

actually here.. read Injuneers post about 14 posts down::::: http://web.camaross.com/forums/showt...&highlight=pcv HA

 

read the post carefully ... the guy was running two breathers, and the pcv system.So it was sucking clean air back i nto the intake. the pcv system does recirculate back into the intake stream( thats how it creates suction). A breather doesnt put air back into the intake stream.
breather/pcv operate operate differently

 

I was still running my PCV valve... i said nothing about taking it off.. LOL

 

I don't see anyone here talking about running two breathers. In all cases, what people are doing is pulling the clean/measured air supply line off the passenger side valve cover, and replacing it with a breather/unmeasured air supply.

The PCV valve evacuates any air that comes into the crankcase, and dumps it into the intake manifold. Any air that has passed through the MAF (as with the stock TB-to-valve cover line) has been measured by the MAF and the PCM had added the fuel to match. Any air that entered through a breather has not been measured by the MAF, and the PCM will NOT supply the fuel to match the "breather" air. The O2 sensors see the mixture go to the lean side, and compensates by raising the long term fuel corrections.

Not sure why the breather would contribute to "split" BLM's????

 

thats what i was talking about