Throttle Position Sensor - Revised Inspect & Adjustment

Bulletin No.: 001/94
Issued: 2/18/94
Revised: 3/9/94

Category
F

Applicable Model/s
See Below

Subject:
INSPECTION AND ADJUSTMENT PROCEDURES FOR THE THROTTLE POSITION SENSOR

The revised section of this bulletin is indicated by an asterisk (*). Replace the original bulletin with this revised copy.
APPLICABLE MODELS/VINS
1989-94 MPV
1988-94 929
1990-94 323/Protege
1992-94 MX-3
1990-93 MX-5 MIATA
1992-94 626/MX-6

DESCRIPTION
The following are revised procedures for inspection and adjustment of the throttle position sensor. DO NOT replace the throttle position sensor unless these instructions have been followed and the results indicate replacement. These instructions are consistent for all of the above models. Please make your shop personnel aware of this change by copying and distributing this bulletin. Due to the quantity of workshop manuals involved, revisions will be made as reprinting occurs.





1. Connect a volt meter to the output terminal for the throttle position sensor at the engine control unit. Refer to the chart.
2. Turn the ignition on.
3. Rotate the throttle lever by hand and confirm that the voltage increases smoothly as the throttle valve opens. Refer to the chart.

NOTE:
If using the engine signal monitor and adapter harness to read the voltage, connect the monitor and adapter harness to the engine control unit and the engine signal monitor terminal to the read terminal. Refer to the chart.

INSPECTION PROCEDURE - Idle Switch Refer to the instructions in the workshop manual.

ADJUSTMENT PROCEDURE - Idle Switch Adjust according to the workshop manual.

THROTTLE POSITION SENSOR REPLACEMENT CRITERIA
The position sensor should be replaced only if the following occurs.
1. If the voltage reading are not within specification and there is no problem found with the wiring harness.
2. If the idle switch will not adjust.
3. If the idle switch is normal but the output voltage of the throttle sensor is not within specification.
4. If the idle switch is normal and the throttle sensor output voltage is within specification but the voltage is not reading smoothly or spikes in the voltage appear halfway between fully closed and fully open throttle.

REPLACEMENT PROCEDURE - Throttle Position Sensor*
Replace according to the instructions in the workshop manual.