Major Differences
The major differences between the 3UZ-FE on the ’01 GS430 and the 1UZ-FE engine on the ’00 GS400
are the following:
Engine Proper
• The water passage of the cylinder head has been changed to improve
the flow of the water around the valve seats, thus reducing
the temperature of the combustion chamber.
• The cylinder bore has been increased in size, and the thickness of
the liner has been reduced.
• The shape of the cylinder head gasket has been changed in conjunction
with the increase in the size of the cylinder bore.
• The material of the cylinder head bolts have been changed to increase
their axial tension. As a result, the head gasket’s tightening
has been improved.
• The piston diameter has been increased in size, and its shape has
been optimized to achieve weight reduction.
• The material of the inner surface of the bushing in the small end
of the connecting rod has been changed from lead bronze alloy to
phosphor bronze alloy.
• The material of the sliding surface of the crankshaft bearing has
been changed from kelmet to aluminum alloy.
Cooling System
The shape of the water inlet housing has been optimized to increase
the water flow and to achieve weight reduction.
Intake and Exhaust System
• A resonator and a tuning hole have been provided in the air cleaner
inlet to reduce the amount of intake air noise.
• The air cleaner case has been increased in size to reduce the
amount of intake air sound, and the construction of the air cleaner
element has been optimized to achieve weight reduction.
• A plug-in type air flow meter with a plastic housing has been
adopted for weight reduction.
• A stainless steel exhaust manifold with a single-pipe construction
has been adopted. As a result, the warm-up performance of the
TWC (Three-way Catalytic Converter) has been improved.
• Two TWCs (Three-way Catalytic Converters) have been provided
in the front, and one in the center.
• Ultra thin-wall, high-cell ceramic type TWCs have
Ignition System
The construction of the ignition coil has been
compact and lightweight configuration.
Engine Control System
• Torque activated power train control has been newly adopted for
the control of ETCS-i. Also, the fail-safe control has been reconsidered
with the adoption of the link-less type throttle body.
• A fuel cut control is adopted to stop the fuel pump when SRS driver’s
and front passenger’s airbags are deployed.