Dodge ram truck 3500 1996 Service Manual page 1361

B R
FUEL S Y S T E M 14 - 127
REMOVAL AND INSTALLATION (Continued)
ENGINE SPEED SENSOR
The engine speed (rpm) sensor is located on the
front of engine (Fig. 32). Spacers located behind the
sensor are used to position sensor over the vibration
damper.
SENSOR MOUNTING BOLTS
ST, "
VIBRATION
DAMPER
J9214-69
Fig. 32 Engine Speed Sensor—Diesel
REMOVAL
Before removing the sensor, note the position and
routing of the sensor wiring harness. This routing
must be maintained to prevent wiring from contact­
ing belt or pulleys.
(1) Disconnect the speed sensor pigtail harness
from the main engine wiring harness near the front/
top of engine.
(2) Remove the clip bolts from the sensor pigtail
wiring harness.
(3) Remove the two speed sensor mounting nuts
(Fig. 32).
(4) Remove the speed sensor and its mounting
spacers from the vehicle.
INSTALLATION/ADJUSTMENT
The engine speed sensor uses a slotted hole on one
side (Fig. 33) to adjust its depth. A brass (non-mag­
netic) feeler gauge must be used to adjust the sensor.
Sensor-to-vibration damper air gap is: 1.25 M M
(.049 in.) minimum to 1.30 MM (.051 in.) maximum.
(1) Position speed sensor, its mounting spacers and
two mounting nuts to the engine. Install mounting
nuts finger tight.
(2) Route sensor wiring harness behind engine pul­
leys. Install and tighten wiring harness clip bolts.
Fig. 33 Engine Speed Sensor—Installation
(3) Place the feeler gauge between the sensor and
the vibration dampener.
(4) Gently seat (push down) the sensor until it con­
tacts the feeler gauge. Be sure the sensor is not
near either of the notches (Fig. 32) on the
vibration damper. If sensor is adjusted at or
near these notches, it will be damaged when
engine is started.
(5) Tighten sensor mounting nuts to 24 N-m (18 ft.
lbs.) torque.
(6) Remove feeler gauge.
(7) Connect the sensor electrical connector to the
main engine wiring harness.
THROTTLE POSITION SENSOR
AUTOMATIC TRANSMISSION ONLY
The throttle position sensor (TPS) is used on
the diesel powered engine only when equipped
with an automatic transmission. If the TPS is to
be replaced on a diesel engine, it must be test­
ed/adjusted after replacement.
REMOVAL
(1) Disconnect the electrical connector on bottom of
TPS (Fig. 34).
(2) Remove the two TPS mounting bolts.
(3) Remove the sensor from bracket.
INSTALLATION
(1) Position the TPS to the mounting bracket. The
electrical connector should be facing downward.
NOTE: The TPS is spring loaded. After positioning
the TPS to its mounting bracket, rotate the TPS on
the bracket in a counterclockwise direction until the
two bolt holes align.
(2) Install and tighten two bolts.