Could be maf or tps. Here are some test procedures:
Volume Air Flow (VAF) MeterOPERATION This component is used on 22R-E, 1FZ-FE, 3VZ-E and 3F-E engines.
This meter measures the amount of air flowing through the intake system. It is used by the ECM to calculate air/fuel mixture.
TESTING 22R-E, 1FZ-FE and 3VZ-E Engines
See Figure 1
Disconnect the wiring from the VAF meter.Using an ohmmeter, measure the resistance between terminals E2 and VS. Resistance should be as follows: 3VZ-E-200-600 ohms
Fig. 1: Attach the ohmmeter to terminals E2 and VS
If the test is not within specification, replace the unit.
Throttle position sensors are usually mounted on the side of the throttle body. The sensor detects the throttle valve opening angle. The voltage of terminal VTA increases in proportion of the opening angle of the throttle valve. The ECM judges the driving conditions from the input signals of the terminals, and uses them as one of the conditions for deciding the air/fuel ratio correction, power increases and fuel cut-off control. 3VZ-E and 1FZ-FE Engines
Confirm that the throttle valve is fully closed.Connect an ohmmeter to terminals IDL and E2. E2 is the bottom terminal, while terminal IDL is positioned directly above it.
Insert a 0.020 in. (0.50mm) thick feeler gauge between the throttle stop screw and lever. Check for continuity between terminals IDL and E2 of the sensor. Continuity should be present.Insert a 0.031 in. (0.80mm) thick feeler gauge between the throttle stop screw and lever. Check for continuity between terminals IDL and E2 of the sensor. Continuity should not be present.