Just brought a A5 steal car thought it was just body work that needed to be done. Took on highway and car was losing power and check engine popped up on me after I brought it. I still took it up to 100 to see if engine was good and it was. Mechanic says need a engine mount and to fix axle. Also it was smoking but it was misfires and coils were replaced! After i fix the engine mount and get a tune up am i looking to see more problems right away ?