This 2004 with A4 trannie has a problem due again to use of Ethanol gas causing huge lean conditions. This is even worse on the day we were test and tuning in about 90 degree weather.

Being his 2004 is about stock like Dave M's ( review his results being tuned within 1 day of Stan's) and you see how much less performance there was due to higher then 10% ethanol gas being used.

This was peaking fuel trims as much as 25% lean with a average part throttle fuel trims of 12% lean !

We had Stan find a gas station that sold normal gas with no Ethanol in it after getting the tank with ethanol used up

Here is a compare of with the Ethanol( on left) and then normal gas without making any changes to the tune
You see fuel trims went richer, HP and torque came up nicely.

I then tweaked the tune to fit using normal gas for best performance

As lean as ethanol makes engine, add 90 degree weather and it kills off performance in a big way