I recently had a Diablo i2 tuner and I had aperformance shop tune my 09 challenger how can I go back into my tuner and check to see if they really tune my vehicle????
Did they dyno tune it? If they did ask for a copy of the dyno sheet. Did you notice if he used your tuner to tune it? Maybe some1 with that tuner can chime in.
To determine if a tune has been loaded into your PCM simply plug in you Diablo tuning tool, select options, then select "Show last tune written". This will show the name of the tune that is in the car assuming one has been loaded.
There are other ways to do this as well but this should be the easiest. It doesn't prove that the tune is "good" just that one was loaded other than stock.