MoTeC M84 - Manual (Page 18)

16 Installation MoTeC
sensor is moved or replaced. It is very important to set these parameters with
the butterfly in exactly the same place each time.
The resistance element inside the sensor may wear due to vibration in high
performance engines which can cause erratic readings. It is best to replace
the throttle position sensor periodically.
Avoid high pressure washing as this may penetrate the seals and damage the
sensor.
For wiring details refer to the appropriate MoTeC drawing.
MAP Sensor
The MAP (Manifold Absolute Pressure) sensor measures Absolute Pressure
(i.e. pressure relative to a vacuum).
0 kPa Absolute = Complete Vacuum
100 kPa = 1 Bar = 14.5 PSI
Atmospheric Pressure at sea level is approximately 100 to 102 kPa,
depending on the weather.
MAP sensors normally produce a voltage between 0 and 5V, depending on
the pressure.
The pressure sensor may be used to measure the inlet manifold pressure or
to measure the barometric pressure depending on the Load Sensing
arrangement detailed earlier.
The ECU Sensor Setup parameters must be set to indicate the type and
pressure range of the sensor.
Avoid severe vibration of the sensor as this can cause fluctuations in the
reading. Do not mount rigidly to the engine. Normally the pressure sensor is
mounted to the vehicle body.
If Used for Manifold Pressure Sensing
For normally aspirated engines use a 100 kPa sensor.
For turbo charged engines a 300 kPa absolute sensor will measure up to 200
kPa (29 psi) of boost (above Atmospheric). If higher boost will be achieved, a
sensor with a higher pressure range will be needed.
The sensor should be connected to the inlet manifold plenum via a short hose
(less than 1m). The sensor should be mounted above the level of the plenum
with the port facing down to avoid moisture accumulating on the sensor
element. The hose should run downwards all the way to the plenum.