For the Yaris family of models exclusively, the 1.0-liter Toyota 1SZ-FE engine was manufactured in Japan between 1999 and 2005. The unit’s gas distribution mechanism was powered by a Morse chain, and the motor had a VVT-i type phase control system only at the inlet.

The engines 2SZ-FE and 3SZ-VE are also part of the SZ family.
The engine was mounted on:
- Toyota Platz XP10 in 1999 – 2005;
- Toyota Yaris XP10 in 1999 – 2005.
Specifications
| Production years | 1999-2005 |
| Displacement, cc | 997 |
| Fuel system | MPI |
| Power output, hp | 69 |
| Torque output, Nm | 95 |
| Cylinder block | cast iron R4 |
| Block head | aluminum 16v |
| Cylinder bore, mm | 69 |
| Piston stroke, mm | 66.7 |
| Compression ratio | 10.0 |
| Features | no |
| Hydraulic lifters | no |
| Timing drive | Morse chain |
| Phase regulator | VVT-i intake |
| Turbocharging | no |
| Recommended engine oil | 5W-30 |
| Engine oil capacity, liter | 3.2 |
| Fuel type | petrol |
| Euro standards | EURO 3/4 |
| Fuel consumption, L/100 km (for Toyota Yaris 2000) — city — highway — combined |
6.9 5.1 5.7 |
| Engine lifespan, km | ~200 000 |
| Weight, kg | 91 |
Disadvantages of the 1SZ-FE engine
This engine is highly sensitive to quality, particularly when it comes to the timing of oil changes;
The hydraulic tensioner’s wedge causes a chain jump and a valve-piston meeting;
Heat may cause air to leak into the intake manifold during extreme frost and vice versa.
Oil is transported through the system for a considerable amount of time after the engine starts due to the pump’s design; adjusting the valves is very challenging because you have to replace the entire drive sleeve.
