If you don't understand CPU, ROM, and microprocessor and LSI chip interfaces, you will probably be in an OBD II car before you figure it out. But I admire your pluck, so good luck.stormmotor wrote:I am looking to buy software to retune the ecu But I need to know where to buy? I do not want to send mine out for someone to do it. I want to learn how to do the retuning for the Q45 and also other cars. I am mechanically inclined But not with this new age electronic