Lately I've noticed, especially during 'spirited' acceleration, that 3rd gear seems to have trouble 'getting over the hump', like it's having a power issue at first. After that, it accelerates fine. For the record, I had the transmission flushed/serviced, cleaned the throttle body, put in a new air filter, and re-flashed the ECU. It's still doing it. Any ideas on what the issue is and how to fix it?

EDIT: The most common transmission issues don't seem to be the problem here. If the clutch was slipping or the tranny filter needed replacing (which was done during the service), all the gears would be affected. Thoughts?

 

After contacting a local guy, I found out that TSB 09-12-12 addresses this exact issue.

 

At least you have identified a possible solution.

 

Yeah, figuring it out is the most nerve-wracking part! Unfortunately, since my car is (long) out of warranty, I have to fix it on my own dime.