Recently we got a nice 2005 Toyota Vitz RS (NCP91) with a manual transmission.
It is great car in all aspects except power delivery and throttle response is pathetic.
We already have 1NZ-FE powered car in the family – Toyota IST and unlike the Vitz RS it is not that pathetic (in fact it is kind of fun to drive).
Yes, I have driven multiple Vitz RS and they were all asthmatic.
So what is so different between IST and RS? IST happens to have cable driven throttle, while RS has drive-by-wire.
Here is where Toyota screwed up and completely ruined the car: they made throttle map to emulate steam roller.
If I was Toyota I would not stick RS badge on the car, it is not a hot hatch simply because it lacks in engine department. Vitz RS should have came out with 1ZZFE at least.
What is even worse they decided to stick this anaemic throttle map on top. As if the car was not boring enough.
After consulting google and various forums I had two minor mod options:
1) Stick a throttle controller
2) Stick a throttle body off 1ZZFE.
I decided to go for second option as it is transparent from end user point of view. There are a few minor hurdles with this mod.