Dodge RAM TRUCK 1500 1995 Service Manual page 1144

14 -12 GENERAL DIAGNOSIS—EXCEPT DIESEL
BR
(3) Disconnect the vacuum line at the PCV valve
(Fig.
33).
Fig. 33 install Orifice Tool
(4) Install the 0.185 inch orifice tool (number 6714)
into the disconnected vacuum line in place of the
PCV valve (Fig. 33).
(5) Disconnect the idle purge vacuum line from fit­
ting at throttle body. This vacuum line is located on
the front of throttle body next to the MAP sensor
(Fig. 34). Cap the fitting at throttle body after vac­
uum line has been removed.
^ FRONT OF ENGINE
BODY J9414-6
Fig. 34 Idle Purge Line
(6) Connect the DRB scan tool to the data link con­
nector (Fig. 35) on the vehicle. Refer to the appropri­
ate Powertrain Diagnostic Procedures service manual
for DRB operation.
(7) Start the engine.
POWERTRAIN CONTROL
MODULE (PCM) J9414-11
Fig. 35 Data Link Connector
(8) Using the DRB scan tool, scroll through the
menus as follows: select—System, select—Engine, se­
lect—Fuel and Ignition, select—Actuator Tests, se­
lect—Engine rpm and select—Minimum Air Flow.
The DRB scan tool will count down to stabilize the
idle rpm and display the minimum air flow idle rpm.
The idle rpm should be between 500 and 900 rpm.
If the idle speed is outside of these specifications, re­
place the throttle body. Refer to Throttle Body in the
Component Removal/Installation section of this
group.
(9) Disconnect the DRB scan tool from the vehicle.
(10) Remove cap from idle purge fitting at throttle
body and install vacuum line.
(11) Remove orifice tool and connect vacuum line
to PCV valve.
(12) Install air cleaner element housing.
VEHICLE SPEED SENSOR TEST
To perform a complete test of the sensor and its cir­
cuitry, refer to DRB scan tool and appropriate Pow­
ertrain Diagnostics Procedures manual.
OXYGEN (02S) SENSOR HEATING ELEMENT TEST
To perform a complete test of single or dual 02S
sensor(s) and circuitry, refer to DRB scan tool and
appropriate Powertrain Diagnostics Procedures man­
ual. To test the 02S sensor only, refer to the follow­
ing:
On 3.9L V-6 and 5.2/5.9L V 8 LDC engines, the sin­
gle 02S sensor is located on the right exhaust down
pipe (Fig. 36).
On both the 5.9L V-8 HDC and 8.0L V-10 engines,
the dual 02S sensors are located on each (left and
right) exhaust down pipe (Fig. 37).
The 02S heating element can be tested with an
ohmmeter as follows:
Disconnect the 02S sensor connector. Connect the
ohmmeter test leads across the white wire terminals
of the sensor connector. Resistance should be be-