Chrysler PT Cruiser Service & Repair Manual page 1334

14 - 38 FUEL INJECTION
IDLE AIR CONTROL MOTOR (Continued)
applied to the O-RINGS ONLY (Fig. 34) to aid
assembly. Use care when removing hoses to prevent
damage to hose or hose nipple.
Fig. 34 O-RINGS
1 - O-rings
(1) The new idle air control motor has a new
O-ring installed on it. For 2.4L only, if pintle mea-
sures more than 1 inch (25 mm) it must be retracted.
Use the DRBIII Idle Air Control Motor Open/Close
Test to retract the pintle (battery must be connected.)
(2) Carefully place idle air control motor into
throttle body.
(3) Install mounting screw(s). Tighten screws to 2
N·m (17 in. lbs.) torque.
(4) Connect electrical connector to idle air control
motor.
(5) Connect negative cable to battery.
INLET AIR TEMPERATURE
SENSOR
DESCRIPTION
The IAT Sensor is a Negative Temperature Coeffi-
cient (NTC) Sensor that provides information to the
PCM regarding the temperature of the air entering
the intake manifold (Fig. 35).
OPERATION
Inlet/Intake Air Temperature (NGC)
The Intake Air Temperature (IAT) sensor value is
used by the PCM to determine air density.
The PCM uses this information to calculate:
• Injector pulse width
• Adjustment of ignition timing (to prevent spark
knock at high intake air temperatures)
Battery Temperature (SBEC Vehicles without
Battery Temperature sensor)
The inlet air temperature sensor replaces the
intake air temperature sensor and the battery tem-
perature sensor. The PCM uses the information from
the inlet air temperature sensor to determine values
for the PCM to use as an intake air temperature sen-
sor and a battery temperature sensor.
The battery temperature information along with
data from monitored line voltage (B+), is used by the
PCM to vary the battery charging rate. System volt-
age will be higher at colder temperatures and is
gradually reduced at warmer temperatures.
The battery temperature information is also used
for OBD II diagnostics. Certain faults and OBD II
monitors are either enabled or disabled depending
upon the battery temperature sensor input (example:
disable purge, enable LDP). Most OBD II monitors
are disabled below 20°F.
REMOVAL
The sensor is located in the clean air duct.
(1) Unlatch or unbolt the air cleaner lid.
(2) Lift air cleaner lid and reposition.
(3) Disconnect the negative battery cable.
(4) Disconnect electrical connector from the sensor
(Fig. 35).
Fig. 35 Inlet Air Temperature Sensor
1 - INLET AIR TEMPERATURE SENSOR
(5) Remove the sensors.
INSTALLATION
The sensors is in the air inlet tube.
(1) Install sensor.
(2) Attach electrical connector to sensor.
(3) Connect the negative battery cable.
(4) Install the air cleaner lid..
PT