Running "Lean" with a Resistor Divider on the Air Temp Sensor

[tjts1]

http://autospeed.com/cms/A_110350/article.html

[tasdrouille]

That's what I wanted to read from you Johnny. So the iats input is not flat out ignored in closed loop. It's corrected by the the output of the o2s. You said earlier that fuel tables are a starting point and then the o2s is god. Yup, but which cell is picked in the table is up to the different sensors, then corrected by the o2s.

How many fuel tables are there? I thought there was a base fuel table that is used without o2s correction in open loop, and this same table affected by long term fuel trim and short term fuel trim values in closed loop.

As far as timing goes you are totally right. It may of may not keep the timing advance. But I have the feeling that knock sensors equipped cars are not all necessarily on the bleeding edge of detonation. I'm gonna try it on my elantra, which is ks equipped, as soon as I can find spare connectors for my mafs (the iats is in my mafs) as I don't want to splice wires on a car under warranty.

On the TDI on the other hand, the iats resistor mod is good for a 2 degrees advance at part load, and quite a change in driveability. But it's a totally different kind of beast I agree.

[JohnnyGrey]

How many fuel tables are there? I thought there was a base fuel table that is used without o2s correction in open loop, and this same table affected by long term fuel trim and short term fuel trim values in closed loop.

It varies from one ECU to the next. The axes of the tables vary according to which sensors are present. For example, my 2.2L does not have a MAF sensor, so it relies on a MAP sensor. The fuel table could also be 3 or 4 dimensional.