1993 CHEVROLET DYNASTY service

(2) With engine running, move test probe along
entire length of all cables (approximately 0 to 1/8
inch gap). If punctures or cracks are present there
will be a noticeable spark jump from the faulty area
to the probe. Cracked, leaking or faulty cables should
be replaced. Use the following procedure when removing the
high tension cable from the spark plug. First, remove
the cable from the retaining bracket. Then grasp the
terminal as close as possible to the spark plug. Ro-
tate the cover (boot) slightly and pull straight back.
Do not use pliers and do not pull the cable at an
angle. Doing so will damage the insulation, cable
terminal or the spark plug insulator. Wipe spark
plug insulator clean before reinstalling cable
and cover. Resistance cables are identified by the words Elec-
tronic Suppression .
Use an ohmmeter to check cables for opens, loose
terminals or high resistance. (a) Remove cable from spark plug.
(b) Remove cable from the coil tower.
(c) Connect the ohmmeter between spark plug
end terminal and the coil end terminal. Resistance
should be within tolerance shown in the cable re-
sistance chart. If resistance is not within tolerance,
replace cable assembly. Test all spark plug cables
in same manner.
SPARK PLUG SERVICE
When replacing the spark plug cables, route the ca-
bles correctly and secure them in the appropriate re-
tainers. Incorrectly routed cables can cause the radio
to reproduce ignition noise. It can also cause cross ig-
nition of the spark plugs or short circuit the cables to
ground.
SPARK PLUG REMOVAL
Always remove cables by grasping at boot, rotating
the boot 1/2 turn, and pulling straight back in a
steady motion. (1) Prior to removing the spark plug spray com-
pressed air around the spark plug hole and the area
around the spark plug. (2) Remove the spark plug using a quality socket
with a rubber or foam insert. (3) Inspect the spark plug condition. Refer to
Spark Plug Condition in this section.
SPARK PLUG GAP ADJUSTMENT
Check the spark plug gap with a gap gauge. If the
gap is not correct, adjust it by bending the ground
electrode (Fig. 6).
SPARK PLUG INSTALLATION
(1) To avoid cross threading, start the spark plug
into the cylinder head by hand. (2) Tighten spark plugs to 28 N Im (20 ft. lbs.)
torque. (3) Install spark plug cables over spark plugs.
IDLE RPM TEST
WARNING: BE SURE TO APPLY PARKING BRAKE
AND/OR BLOCK WHEELS BEFORE PERFORMING
ANY ENGINE RUNNING TESTS.
Engine idle set rpmshould be tested and recorded
as it is when the vehicle is first brought into shop
for testing. This will assist in diagnosing complaints
of engine stalling, creeping and hard shifting on ve-
hicles equipped with automatic transaxle. Refer to the
Throttle Body Minimum Airflow procedures in Group
14.
IGNITION TIMING PROCEDURE
Ignition timing cannot be changed or set on Turbo
III, 3.3L or 3.8L engines. For diagnostic information,
refer to the DRBII scan tool and the appropriate
Powertrain Diagnostics Procedures manual.
CABLE RESISTANCE CHART
Fig. 6 Setting Spark Plug GapÐTypical
Ä IGNITION SYSTEMS 8D - 41

CRANKSHAFT POSITION SENSORÐTURBO III EN-
GINE
REMOVAL
(1) Remove throttle body.
(2) Remove inter-cooler to turbo-charger air hose.
(3) Disconnect crank timing sensor pick-up lead at
wiring harness connector (Fig. 7).
(4) Remove crank timing sensor retaining bolt.
(5) Pull crank timing sensor straight up out of the
transaxle housing.
INSTALLATION
(1) Install sensor in transaxle. Push sensor down
until contact is made with the transaxle housing. Hold
the sensor in this position. Install and tighten retain-
ing bolt to 16 N Im (145 in. lbs.) torque.
(2) Connect electrical connector to sensor.
CRANKSHAFT POSITION SENSORÐ3.3L AND 3.8L
ENGINES
REMOVAL
(1) Disconnect crankshaft position sensor electrical
connector from the wiring harness connector (Fig. 8). (2) Remove sensor retaining bolt.
(3) Pull crankshaft position sensor straight up out of
the transaxle housing.
INSTALLATION
If installing the original sensor, clean off the
old spacer on the sensor face. A NEW SPACER
must be attached to the sensor face before instal-
lation. If the sensor is being replaced, confirm
that the paper spacer is attached to the face of
the new sensor (Fig. 9). (1) Install sensor in transaxle and push sensor down
until contact is made with the drive plate. While holding the sensor in this position, and install and
tighten the retaining bolt to 12 N
Im (105 in. lbs.)
torque. (2) Connect crankshaft position sensor electrical
connector to the wiring harness connector.
CAMSHAFT POSITION SENSOR SERVICEÐTURBO
III ENGINE
REMOVAL
(1) Disconnect camshaft position sensor connector
from wiring harness (Fig. 10). (2) Remove camshaft position sensor retaining bolt
and remove sensor.
INSTALLATION
If installing the original sensor, clean off the
old spacer on the sensor face. A NEW SPACER
must be attached to the face before installation.
If the sensor is being replaced, confirm that the paper
spacer is attached to the face (Fig. 11). (1) Install sensor in the cylinder head and push
sensor down until contact is made with the camshaft
gear. While holding the sensor in this position, install
and tighten the retaining bolt 16 N Im (145 in. lbs.)
torque. (2) Connect electrical connector to the sensor.
Fig. 7 Crankshaft Position Sensor ServiceÐTurbo III Engine
Fig. 8 Crankshaft Position SensorÐ3.3L and 3.8LEngines
Fig. 9 Crankshaft Position Sensor and Spacer
8D - 42 IGNITION SYSTEMS Ä

CAMSHAFT POSITION SENSORÐ3.3L AND 3.8L
ENGINES
REMOVAL
(1) Disconnect camshaft position sensor electrical
connector from the wiring harness (Fig. 12). (2) Remove engine mount support bracket.
(3) Loosen camshaft position sensor retaining bolt
enough to allow slot in sensor to slide past the bolt. (4) Pull sensor up out of the chain case cover. Do not
pull on the sensor lead. There is an O-ring on the
sensor case. The O-ring may make removal difficult. A
light tap to top of sensor prior to removal may reduce
force needed for removal.
INSTALLATION
If installing the original sensor, clean off the
old spacer on the sensor face. A NEW SPACER
must be attached to the face before installation.
Inspect O-ring for damage, replace if necessary. If the
sensor is being replaced, confirm that the paper spacer is attached to the face and O-ring is posi-
tioned in groove of the new sensor (Fig. 13).
(1) Apply a couple drops of clean engine oil to the
O-ring prior to installation. Install sensor in the
chain case cover and push sensor down until contact
is made with the camshaft timing gear. While hold-
ing the sensor in this position, install and tighten
the retaining bolt 14 N Im (125 in. lbs.) torque.
(2) Connect camshaft position sensor electrical con-
nector to harness connector. Position connector away
from the accessory belt. (3) Install engine mount support bracket.
IGNITION COIL SERVICEÐTURBO III ENGINE
(1) Remove spark plug cables from coil (Fig. 14).
(2) Remove electrical connector from coil pack.
(3) Remove ignition coil fasteners.
(4) Reverse the above procedure for installation.
Tighten fasteners to 12 N Im (105 in. lbs.) torque.
IGNITION COILÐ3.3L AND 3.8L ENGINE
(1) Remove spark plug cables from coil (Fig. 15).
(2) Remove ignition coil electrical connector.
(3) Remove ignition coil mounting screws.
(4) Remove ignition coil.
Fig. 12 Camshaft Position Sensor LocationÐ3.3L and 3.8L Engine
Fig. 13 Camshaft Position SensorÐ3.3L and 3.8L Engines
Fig. 10 Camshaft Position Sensor LocationÐTurboIII Engines
Fig. 11 Camshaft Position SensorÐTurbo III Engine
Ä IGNITION SYSTEMS 8D - 43

Reverse the above procedure for installation.
Tighten mounting screws to 12 N Im (105 in. lbs.)
torque.
MANIFOLD ABSOLUTE PRESSURE (MAP)
SENSORÐTURBO III ENGINE
The map sensor mounts to the right front fender
(Fig. 16). (1) Remove vacuum hose from MAP sensor.
(2) Remove MAP sensor mounting screws.
(3) Remove electrical connector from sensor.
(4) Reverse procedure for installation.
MANIFOLD ABSOLUTE PRESSURE (MAP)
SENSORÐ3.3L AND 3.8L ENGINES
The alignment of the MAP sensor is critical to the
sensors performance. The top of the sensor is marked
This Side Up (Fig. 17). (1) Disconnect electrical connector from MAP sen-
sor. (2) Remove sensor by unscrewing from the intake
manifold (Fig. 17). (3) Reverse the above procedure for installation.
Fig. 14 Ignition Coil ServiceÐ2.2L Turbo III
Fig. 15 Ignition Coil Removal and Installation
Fig. 16 MAP SensorÐTurbo III Engine
Fig. 17 Manifold Absolute Pressure Sensor
8D - 44 IGNITION SYSTEMS Ä

IGNITION SWITCH
IGNITION SWITCH AND KEY CYLINDER SERVICE
The ignition switch is located on the steering col-
umn. The Key In Switch is located in the ignition
switch module. For diagnosis of the Key In Switch,
refer to Section 8M.
REMOVAL
If the vehicle has a floor mounted gear shifter,
place the selector in the Park position. (1) Disconnect negative cable from battery.
(2) If the vehicle has a tilt column, remove the tilt
lever by turning it counterclockwise. (3) Remove upper and lower covers from steering
column.
(4) Remove ignition switch mounting screws. Use
tamper proof torx bit Snap-on TTXR15A2, TTXR20A2
or equivalent to remove the screws (Fig. 1). (5) Gently pull switch away from the column. Release
connector locks on the 7 terminal wiring connector,
then remove the connector from the ignition switch.
(6) Release connector lock on the 4 terminal con-
nector, then remove the connector from the ignition
switch. (7) To remove the key cylinder from the ignition
switch: (a) Insert key in the ignition switch. Turn the
key to the LOCK position. Using a small screw-
driver, depress the key cylinder retaining pin until
it is flush with the key cylinder surface (Fig. 2). (b) Rotate the key clockwise to the OFF position.
The key cylinder will unseat from the ignition
switch (Fig. 3). When the key cylinder is unseated,
it will be approximately 1/8 inch away from the ig-
nition switch halo light ring. Do not attempt to
remove the key cylinder at this time. (c) With the key cylinder in the unseated posi-
tion, rotate the key counterclockwise to the lock po-
sition and remove the key. (d) Remove key cylinder from ignition switch
(Fig. 4).
INSTALLATION
If the vehicle has a floor mounted gear shifter,
place the selector in the Park position.
IGNITION SWITCH DESIGNATIONS
Fig. 1 Ignition Switch Screw Removal
Fig. 2 Key Cylinder Retaining Pin
Ä IGNITION SYSTEMS 8D - 45

INSTRUMENT PANEL AND GAUGES
CONTENTS
page page
AA BODY .............................. 1
AC AND AY BODIES .................... 23 AG AND AJ BODIES
.................... 42
AP BODY ............................. 58
AA BODY INDEX
page page
Cluster and Gauge Service and Testing ........ 2
Electronic Cluster ........................ 13
Fuel GaugeÐFlexible Fuel .................. 2
Gauges ................................. 7
General Information ........................ 1 Instrument Panel
......................... 21
Interior Lamp Replacement ................. 21
Mechanical/Electronic Cluster Removal ......... 5
Switch and Panel Component Service ......... 15
GENERAL INFORMATION
INSTRUMENT CLUSTERS
There are three instrument cluster assemblies. The
mechanical clusters incorporate magnetic type
gauges. The electronic instrument cluster incorpo-
rates, a digital speedometer/odometer and electronic
analog gauges. The mechanical Lo-Line instrument cluster has
magnetic type gauges for coolant temperature, fuel
level and charging system voltage (Fig. 1).
The mechanical Hi-Line instrument cluster has
magnetic type gauges for oil pressure, coolant tem-
perature, charging system voltage and fuel level. The
premium instrument cluster also has a tachometer
(Fig. 2). If the ignition switch is in the OFF position each
gauge will show a reading, except for the volt gauge. However the readings are only accurate when the ig-
nition switch is in the ON position.
TACHOMETER DRIVE MODULE
The tachometer drive module is an electronic mod-
ule used to drive a magnetic tachometer in a conven-
tional instrument cluster.
ELECTRONIC DIGITAL CLOCK
The electronic digital clock is in the radio. The
clock and radio each use the display panel built into
the radio. A digital readout indicates the time in
hours and minutes whenever the ignition switch is in
the ON or ACC position. When the ignition switch is in the OFF position, or
when the radio frequency is being displayed, time
keeping is accurately maintained.
MESSAGE CENTER
The message center includes the graphic display of
the car with illuminating graphics for: low wind-
Fig. 1 Instrument Cluster
Fig. 2 Instrument Cluster With Tachometer
Ä INSTRUMENT PANEL AND GAUGES 8E - 1

shield washer fluid, door ajar for each door, and
trunk ajar. It also includes headlamp out, tail lamp
out, and brake lamp out warning lights (Fig. 3),
these lights are operated by a lamp outage module.
When there is no message center there is no door
ajar function.
TRAVELER
The traveler is a five function trip computer. It
uses vacuum fluorescent displays to display: trip
miles, instantaneous fuel economy, trip elapsed time,
trip average fuel economy and, estimate distance to
empty. It is located in the message center (Fig. 4).
WARNING LAMPS AND INDICATOR LIGHTS
The mechanical instrument cluster assemblies
have warning lamps and indicator lights for ten dif-
ferent systems. These include left and right turn sig-
nals, low fuel level, low oil pressure, high beam indicator, seat belt reminder, brake system, malfunc-
tion indicator (check engine) lamp, check gauges, an-
ti-lock system and air bag system indicator. The low oil pressure indicator replaces the Check
Gauges indicator in the cluster assembly without a
tachometer. In the cluster assembly with tachometer, Check
Gauges indictor illuminates in a warning situation.
This will notify driver to check for a problem in cool-
ant temperature, oil pressure or electrical systems.
CLUSTER AND GAUGE SERVICE AND TESTING
CAUTION: Disconnect battery cable. Before servic-
ing the instrument panel. Reconnect battery cable
when power is required for test purposes.
FUEL GAUGEÐFLEXIBLE FUEL
The flexible fuel vehicle uses a dampened fuel
gauge. Methanol fuel causes erratic gauge movement
if the proper gauge is not used. The unique fuel gauge may be identified by either
a green logo on the face of the gauge or by checking
the part number. Remove cluster from the instru-
ment panel and check the part number on top of the
cluster. Refer to Mechanical/Electronic Cluster Re-
moval for proper procedures. Refer to parts catalog
for proper part number.
Fig. 3 Message Center
Fig. 4 Traveler and Message Center
8E - 2 INSTRUMENT PANEL AND GAUGES Ä

SENDING UNIT TEST
When a problem occurs with a cluster gauge, be-
fore disassembling the cluster to check the gauge,
check for a defective sending unit or wiring. (1) Sending units and wiring can be checked by
grounding the connector leads, at the sending unit,
in the vehicle. (2) With the ignition in the ON position; a
grounded input will cause the oil, fuel or tempera-
ture gauge to read at or above maximum.
LOW OIL PRESSURE/CHECK GAUGES WARNING LAMP TEST
The low oil pressure/check gauges warning lamp
will illuminate when the ignition key is turned to
the ON position without starting the vehicle. In the cluster assembly without tachometer, the
low oil pressure lamp will illuminate if the engine oil
pressure drops below a safe oil pressure level. In the cluster assembly with tachometer, the Check
Gauges warning lamp illuminates when there is a
problem in oil pressure level, high engine tempera-
ture or low voltage. To test the system turn ignition key to the ON po-
sition. If the lamp fails to light, inspect for a broken
or disconnected wire at the oil pressure combination
unit, which is located at the front of the engine (Figs.
5 and 6). If the wire at the connector checks good,
pull connector loose from the switch terminal and
with a jumper wire ground connector to the engine
(Fig. 7). With the ignition key turned to the ON po-
sition check the warning lamp. If lamp still fails to
light, inspect for a burned out lamp or disconnected
socket in the cluster.
COMBINATION OIL UNIT TEST
The combination oil unit has two functions:
(1) The normal closed circuit keeps the oil pressure
warning/check gauges lamp on until there is oil pres-
sure (Fig. 7). (2) The sending unit provides a resistance that
varies with oil pressure. (3) To test the normally closed oil lamp circuit, dis-
connect the locking connector and measure the resis-
tance between the switch terminal and the metal
housing. The ohmmeter should read 0 ohms. Start
the engine. (4) If there is oil pressure, the ohmmeter should
read an open circuit. (5) To test the sending unit, measure the resis-
tance between the sending unit terminal and the
metal housing. The ohmmeter should read open.
Start the engine. (6) The ohmmeter should read between 30 to 55
ohms, depending on engine speed, oil temperature,
and oil viscosity. (7) If the above results are not obtained, replace
the switch.
BRAKE SYSTEM WARNING LAMP TEST
The brake warning lamp illuminates when parking
brake is applied with ignition key turned ON. The
same lamp will also illuminate should one of the two
service brake systems fail when brake pedal is ap-
plied. To test system turn ignition key ON, and ap-
ply parking brake. If lamp fails to light, inspect for a
burned out lamp, disconnected socket, a broken orFig. 5 Combination Oil Unit (2.5L)
Fig. 6 Combination Oil Unit (3.0L)
Fig. 7 Combination Oil Unit Test
Ä INSTRUMENT PANEL AND GAUGES 8E - 3