Well the open breather cap causes a "LEAN BANK ONE, LEAN BANK TWO" code and the CHECK ENGINE LIGHT to come on. I have chips from JIM and Sal and they have both been told numerous times that I had an open breather cap but non of their reburns, and I have had a bunch, kept the CHECK ENGINE LIGHT from coming on. I finally got tired of disconnecting the battery to reset the light every day so I went back to the closed cap. I was greeted by two plesant surprises. The light didn't come on any more and my truck quick using 1 qt of oil every three thousand miles. The hell with the "open breather cap."
noelvm

 

Are we blocking off the hose that goes from the drivers valve cover to the rubber air inlet to the blower? I would think that would make a difference. I think that that hose is the main vent for crankcase blowby in the stock configuration. I plug that line with a ball bearing when I run the Valve cover filter. If you dont plug that line, you just created a HUGE air leak into the metered air flow?

Andy

 

there may be a leak but the computer is compensating for it apparently right?

 

So the question is, do I have to have my chip which was originally burnt for the breather cap reburnt now because I put the stock oil cap back on?

 

brasil

no, you don`t have to have your chip reburned if you remove the breather cap and go back to the stock cap, your truck will just run a little bit richer with the stock cap in place.



awhittle

you are exactly right, when I run a breather cap I have one on each side and plug the hole in the rubber air inlet hose.

Larry.

 

I see alot of people putting the stock back on. I guess I've let others do research for me and have saved myself $20 that can go to buying porkchops.

 

Agreed.

 

I quit using the breather cap for two reasons: 1.) I got sick and tired of the SES lights [lean codes--and yes my chip was burned for the cap, and reburned and . . .] and 2.) on a back to back dyno I lost hp with the breather cap verses the stock oil cap. Others have dyno'd with and without the breather cap and lost little or no hp.

Greg

 

Since the breather cap is purchased for its "bling", and not its performance, why don't you guys just seal the cap from the inside? Then it looks great in the engine compartment (bling), and does not affect tuning. At least thats what we do/recommend.

No sense wasting a chromy good looking part by removing it.

 

Glad to see ya have a sense of humor

 

I had 2 breathers on my truck (driver/passenger). Never had one SES light come on or have any codes thrown. I never had oil in my intake/plenum either.

Passenger side

Driver side


--Joe

 

I only have the oil cap replacement breather; but, I've not had an SES light with mine either. I does keep the oil out of my intake. Without it I get oil all the way down to the MAF. Nasty!