Just got a 2010 sedan had it for 3 days and it did this really weird and rather disturbing thing where it wouldn't accelerate the rpms where jumping round between 1500 to 2500 RPMs or so and wouldn't accelerate. Let out of gas rpms drop super low then steady out and car would cruise just fine with very little throttle input. Push gas again back to crazy RPM jumps and no power let it go and stables out and would cruise with very little input. Got it to house put in park pushed gas and it wouldn't rev up it would do the same thing as on the highway. Turned it off went in house. Came back out and hour later started it up and it runs like a scalded dog. Took it out just beat on it to see if it would do it again...and nothing. Its going to shop tomorrow but how in world can they fix something that its not doing. Called my bank and they will not pay the loan until I have given them the yes its fixed. The problem is I don't think the dealership will have the slightest idea as to how. Any insight or ideas would be great. I really want a G37 but part of me doesn't want this one.