You do not calibrate the sensor on decel.....you do a free air calibration with the sensor either out of the exhaust stream in free air, or you let the car sit for 12 hours without being ran and do a free air calibration with the sensor still installed before you crank then engine after it's been sitting.

Free air calibrations are very very important to a sensors accuracy. If there are any trace gasses around the sensor when you calibrate it, it will throw off the calibration severly.

You are reading o2% on decel because on decel the injectors shut off after their initial over-run delay. When this happens, you will read lean and then should go into o2%. Of course, the Innovate LC-1 wideband is what we are talking about, because the LC-1 is the only wideband controller that reads like this and allows a free air calibration mode.

DO NOT tune until you have properly done a free air calibration, using the methods i stated above.

CJ

 

You can calibrate the LC-1 on decel just fine. Klaus has even recommended it on the forums here and it is in the manual.

 

I pulled mine out of the exhaust after the car sat in an open garage long enough for it to cool off. its not that hard with a floor jack(use jack stands please). I just cant bring myself to trust the decel method just cause of crankcase gases, ect.

 

correct, on decel the throttle plate closes, the injectors shut off and the engine becomes a big air pump that flushes everything else out.

 

I believe the calibration is correct. I think the mix has richened up a bit because I did the initial tuning while it was cooler outside. It's been fairly warm lately. The timing changes I've made recently may be compounding the effect.

Should I make a correction to the temperature compensation map or readjust the fuel tables. If I adjust the fuel tables, it'll lean out when it gets cool/cold again.

 

TXS Tuna Pro also supports free air calibration AND ONLY free air calibration for the reasons iTune mentioned. Sure it takes longer to do a free air cal, but if you are not sure about the calibration it the best way to go.

 

you're right, timing changes will absolutely affect the AFR, I would correct for this and get back to enjoying the car

 

Anyone have any comments on this subject? Even the first logs that I posted in this thread are richer than the ones I took a couple of months ago. It's likely due to the fact that it was cold then(~35*F) and it's considerably warmer now(~70*F). I guess the real question is can/should you run a different AFR in different air temperatures?

 

the AFR really shouldn't drift much with a stock MAS since our cars have a intake temp sensor, barometric pressure sensor and measure airflow to compensate for altitude and weather changes.

 

Yes AFR's change with weather. Mine swing by more than 0.5. There is a thread discussing that on here. There's also temp correction table you can play with to reduce this effect, or to dial it just the way you like instead of having different tunes.

And yes you han be leaner when its colder outside and need to be richer when its hot. That's the point and reason for the air temp correction table to exist.