Yes the air does lean out the mixture, but it is not to be considered "exta". The ECU has calculated it in already. Also I was thinking when you took your a/f ratio readings, you are suppose to read them at wide open throttle (WOT). The blow off valve/dv would not even factor in until you released your foot off the gas (a normally rich period anyways) compounded by the lack of additional air from the BOV).

 

rethink that bro. if th bov doesnt effect the fuel mixture at wot then it seems there is no problem with a bov. if that thinking were true it would explain the normal a/f readings


BTW we agree to disagree right?

 

The ECU takes approx 200 miles to learn itself.

 

yeah and it takes about 2000 miles to foul things at that minimal of a ratio change. dont you think. i dont think the bov makes that big of a difference in the mixture. do you? were not recycling that much air.

 

No not THAT much. It would take thousands of miles to make a difference.


You're right the BOV has no bearing on WOT conditions. It is when you release the throttle. Just because it isn't at WOT doesnt mean the engine isn't still burning fuel/air or combustion isn't taking place.

 

...somehow i forgot about the ECU learning...
thanks jest

 

yeah you prbably forgot cuz you drive a ford.

and yeah the a/f mixtures wouldnt be affected under part throttle cuz the bov is closed. the only time it would run rich is the slight fraction of a second the bov is open. then all is well. catch my drift?

 

Hey if you do a lot of city driving, that fraction of a second can add up.

 

fords do the same thing...but yeah, i'll be willing to bet it's not as advanced.. it's close

 

but not enough to cause any damage to the engine. i see how making the one mod you do a bov would mess it up. the stock plugs would foul but if you got better plugs that ignite the mixture better then there would be no left over unburned gasoline. plus a bov sprays all the oil fronm the intake into the air.