TOYOTA PREVIA 91-97 REPAIR MANUAL

4-28 DRIVEABILITY AND EMI3SIONS CONTROLS

To install:

2. Make certain the throttle plate is fully closed. With the throttle
   held in its normal orientation, place the sensor onto the throttle bod
   that the electrical connector is in the correct position.


3. Turn the sensor clockwise as shown and temporarily install th
   retaining screws.


4. Adjust the throttle position sensor.

ADJUSTMENT

body

so

1991-94 Models

I See Figure 88

1. Loosen the sensor screws.


2. Insert a 0.0325 inch (0.83mm) feeler gauge between the throttle stop
   screw and lever.


3. Connect an ohmmeter to terminals IDL and E2.


4. Gradually turn the sensor clockwise until the ohmmeter deflec
   then tighten the screws.


5. Using a 0.398 inch (0.60mm) feeler gauge between the throttl
   and lever, verify with an ohmmeter that there is continuity.

sand

stop

Fig. 89 Loosen the two throttle position sensor screws

Fig. 8(1 Gradually turn the throttle position sensor clockwise

then tighten the retaining screws

6. Using a 0.413 inch (1.05mm) feeler gage between the throttle
   screw and lever, verify with an ohmmeter that there is not continuity.


7. If none of the test is as specified, replace the sensor.

1995-97 Models

I See Figures 89 and 90

1. Loosen the sensor screws. Apply vacuum to the throttle open*
   equipped.


2. Insert a 0.029 inch (0.073mm) feeler gauge between the thrott |e stop
   screw and lever.


3. Connect an ohmmeter to terminals IDL and E2 of the sensor.


4. Gradually turn the sensor clockwise until the ohmmeter deflec |s and
   then tighten the screws.


5. On the 1995 models:
   a. Using a 0.024 inch (0.060mm) feeler gauge between the mettle
   stop and lever, verify with an ohmmeter that there is continuity.
   b. Using a 0.041 inch (1.05mm) feeler gage between the throt
   screw and lever, verify with an ohmmeter that there is not continu


6. On the 1996-97 models:

estop

y.

Ohmmeter

Feeler

Gauge

Vacuum

Fig. 90 Adjusting the TPS using an ohmmeter and feeler

gauge—1995-97 models

a. Using a 0.020 inch (0.050mm) feeler gauge between the throttle

stop and lever, verify with an ohmmeter that there is continuity.

b. Using a 0.037 inch (0.095mm) feeler gage between the throttle

stop screw and lever, verify with an ohmmeter that there is not continuity.

7. If none of the test is as specified, replace the sensor.

Camshaft Position Sensor

OPERATION

The Camshaft Position sensor (G signal) consists of a signal plate

and pickup coil. The G signal plate has one tooth on its outer circumfer-

ence and is built into the distributor. When the camshafts rotate, the pro-

trusion on the signal plate and the air gap on the pickup coil change,

causing fluctuations in the magnetic field and generating an electromo-

tive force in the pickup coil. The NE signal plate has 34 teeth and is

mounted on the crankshaft. The NE signal sensor generates 34 signals

every engine revolution. The ECM detects the standard crankshaft angle

based on the G signals and the actual crankshaft angle and the engine

speed by the NE signals.