i just installed the v stack with k&n filter instead of autozone filter.

my afr reading was 14.7-15 when cruising
and 12.4-12.8 when open throttle

now its 13.9 -14.7 cruising
and 11.3-12.4 when open throttle


does that mean that whatever i did is getting me less air and choking the engine?

or can it be warmer weather?
i tuned it about 2-3 months ago when it wasnt very warm.

 

Doesn't look lean to me. You added more air and now the ECU is dumping more fuel to compensate.

 

its open loop tune if i added more air wouldnt it be leaner because fuel maps are same and more air is coming into mixture?


also when decelerating i only see fuel cutoff when throttle is completely closed is that how it works? i always thought that fuel cuts off earlier than that.

weird thing innovative ships their units with a serial port when most of new laptops dont have the serial ports anymore...
i was gonna hook it up to my laptop to get a afr readings table but failed lol no serial port on any of my laptops...

 

I haven't gotten into tuning yet so I'm probably not the best person to listen to. But I will say that I'm running richer with no changes made in my setup other than this heatwave.

As for the serial port, I know they have serial to USB adapters.
http://motors.shop.ebay.com/i.html?_...=serial+to+USB

 

Because the hotter the air the thinner. That's why its more rich in hotter weather

 

Simple science. Nice, simple explanation. I like.
I had the erroneous idea that the ECU should totally compensate for this.

 

Im not sure but I believe it should some what as long as you are in closed loop but i'm not positive

 

i might be wrong but i think with a closed loop theres a target afr +/- certain %
and ecu will compensate for it. i ran the car with O2 enabled and afrs were leaner all the way across because ecu adjusts it.

but the engine didnt run as good as in open loop i might try to enable it now to see if o2 would help in hot weather.


i guess i should do a laptop datalog run with regular filter and with v stack to see if theres difference.

 

in open loop the ecu runs solely off the fuel/timing maps and doesnt take the o2 readings into account. you're right that in closed loop it will adjust but only so much.

those a/f readings arent too bad.

 

i was just trying to figure out if v stack made difference lol
but i guess i should collect some more accurate data to tell instead of guessing .
just wanted to confirm that warm weather does affect the readings.

 

The temp. Humidity, Barometric Pres. they can all have effects and even fi you are in closed loop if you have it set to only a low percentage of allowable change from your base map it may not correct the mixture enough to see that same 14.7 you were seeing before

 

i want to enable my O2 sensor for summer time.

where in crome can i see the target afr and the percentage?

do tuners usually set that up when they tune open loop?