Haltech F9A - Manual (Page 21)

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1.3.4. The Throttle Position Sensor (TPS)
The throttle position sensor is mounted to the throttle butterfly shaft to measure its rotation. A
TPS is common on many late model engines and the Haltech sensor should attach with little
or no modification. The throttle shaft must protrude from the side of the throttle body. This
may require the machining of the throttle body or the manufacture of a new throttle shaft. The
inner mechanism of the sensor rotates with the shaft. If the shaft is round then file a flat
surface on the shaft so that it will pass through the sensor assembly. The TPS should be
mounted against the side of the throttle body, using two screws, such that the throttle shaft
and the sensor mechanism can rotate freely. Make sure that the axis of rotation of the
shaft is exactly aligned with the axis of rotation of the sensor. Also, do not use the TPS as
a throttle stop. In either case, the TPS will be damaged. The absolute range of sensor
movement is not important as the sensor can be calibrated using the programming software.
Even if you are going to sense engine load via a MAP sensor, a TPS MUST BE
CONNECTED. The TPS allows the ECU to provide improved throttle response and
driveability.
1.3.5. Route Wiring Harness and Connect Sensors
Lay the main wiring harness out in the engine bay with the sensors mounted to ascertain the
best fit for the harness. Pass the wiring loom through a hole in the engine bay firewall and
into the passenger compartment where the ECU will be mounted. Either use an existing hole
or cut a new hole to suit. Use a rubber grommet or similar device to protect the harness from
being damaged by rubbing on the sharp edge of the hole.
IMPORTANT
• Do not allow the harness to touch hot exhaust parts including manifolds or
turbochargers.
• Try to route the main harness away from high voltage ignition leads. Under no
circumstances run any wiring parallel to, or in contact with the ignition leads.
Hint: Be neat. Run the harness in a tidy fashion. Try to run the harness along paths used by
original wiring. Use nylon cable ties to secure the harness in place, but do not stress the
wiring or connectors.
Once the harness is fitted, connect all the sensors to their appropriate plugs.