If sludge is suspected:

: Provides better engine braking for downhill driving or higher RPMs for acceleration.

If your fuel pump was replaced with a non-OEM unit, the UPD sensor might be missing, incompatible, or improperly seated. Some cheap pumps omit the sensor to save costs—this guarantees a P69B.

The Vitz has undergone several transformations since its 1999 debut, evolving from a simple city car to a sophisticated supermini. トヨタ自動車株式会社 公式企業サイト Design & Aerodynamics:

: For a more economical option, consider second-hand or used parts. Websites, junkyards, and used car parts dealers can be sources for these. However, ensure the part is in good condition and compatible with your vehicle.