Quick update on my Kerma CJAA tune that I installed last weekend.
I did not drive as much this week as I normally do, only 420 miles. My first impressions concerning drivability are fantastic. The car simply pulls strong in any gear. The difference is noticeable and impressive but not over the top nor out of place for a commuter car, which my car is. I can drive just as I always have on my commute and you would not even know the tune was installed.
I have noticed lower exhaust temperatures throughout the whole system including the DPF. My fuel flow is lower all around, from idle to cruise. When rev matching, etc....throttle response is greatly improved. I saw one active regen in that 420 miles, it was substantially shorter in duration then with the software that was previously installed in the vehicle. I was previously experiencing long regens every 200-250 miles, and this was for a vehicle that drove 100 miles per day, mostly highway and high speed rural roads.
As for fuel economy, I saw an increase of approximately 4 miles per gallon hand calculated at the pump. From 41.7 mpg to just shy of 46 mpg. I was impressed with the number considering the tank included some fairly heavy throttle enjoying the new tune as well as some long periods of idling. Even though their accuracy is poor, at 370 miles into the tank the needle was at the half full mark. Compared to normally about 300 miles into the tank pre tune.
The average MPG calculation in the MFD, it might need some slight tweaking with VCDS but in the end I found it to mimic its behavior in indicating slightly high from the factory. I saw averages on my trips from 42-50.5 mpg. As stated prior by others, this tune keeps all factory emissions equipment in tact.
