I have been having issues with my 2003 sedans auto transmission hesitating shifting on hard acceleration after the car was warmed up. Took to infiniti dealership and they diagnosed as bad ignition switch that is losing contact due to body flex under hard acceleration. They are fixing under warranty but this is the first I have heard of this, does anybody have any input? Thanks.

 

That is a new one past me. Maybe a grounding wire upgrade would help?

 

I have a 03.5AT sedan w/ 43,5XX miles, and I haven't encountered any shifting probs with the transmission. If your dealer is diagnosing this problem as a bad ignition switch due to "body flex", then you might also want to ask them to check on your suspension components for worn or loose parts (e.g. bushings, compression rods, CV joints, etc.) It sounds like the ignition switch may not be the definite source of the problem, so get the suspension checked out.