Audi has replaced the 2.0FSi and 2.0TFSi engines with a new 1.8TFSi for the latest 4 cylinder models. The six pot 3.2L remains and in some markets, the 2.7L as well.

The old 2L engines have been phased out as far as the A4 is concerned. I am not too sure about USA but this should be true round the world.

The new 1.8TFSi engine allows Audi to mate it with their 7-speed CVT box, while the old 2.0 engines were paired with 6 speeders. The 2008 A4 is also better equiped and has a much nicer ride. I hope Hertz has switched to this model.

I've tried the A4 with the new 1.8 and find it almost as good as the 2.0 and a bit smoother. It cannot match the six-cyliners for smoothness, though. But the best was an A3 I rented in Barcelona's National Car Rental which came with a 2.0 Turbo-diesel. The torque was fantastic. Beautiful for mountain drives.