1998 DODGE RAM 1500 Evap

4WD SWITCH (MANUAL TRANSFER CASE)-2WAY
CAV CIRCUIT FUNCTION
1 K77 18BR/WT TRANSFER CASE POSITION SENSOR INPUT
2 Z901 18BK GROUND
A/C COMPRESSOR CLUTCH (DIESEL) - BLACK 2 WAY
CAV CIRCUIT FUNCTION
1 C3 18DB/YL A/C COMPRESSOR CLUTCH RELAY OUTPUT
2 Z816 18BK GROUND
A/C COMPRESSOR CLUTCH (GAS) - BLACK 2 WAY
CAV CIRCUIT FUNCTION
1 C3 20DB/YL A/C CLUTCH RELAY OUTPUT
2 Z153 18BK/GY GROUND
A/C HEATER CONTROL C1 - BLACK 16 WAY
CAV CIRCUIT FUNCTION
1 F504 20GY/PK FUSED IGNITION SWITCH OUTPUT (RUN)
2 Z24 18BK/OR GROUND
3 C121 20DB/DG SENSOR GROUND
4 C29 20DB MODE DOOR 2 DRIVER
5- -
6 C21 20DB/LG EVAPORATOR TEMPERATURE SENSOR SIGNAL
7- -
8 E16 20OR/GY PANEL LAMPS DRIVER
9 C61 20DB/LG BLEND DOOR DRIVER
10 C801 20DB/OR MODE DOOR 1 DRIVER
11 C34 20DB/LB COMMON DOOR DRIVER
12 C32 20DB/TN RECIRCULATION DOOR DRIVER
13 C33 20LB/BR (DUAL ZONE) PASSENGER BLEND DOOR DRIVER
14 - -
15 C110 20DB/LB DEFOGGER RELAY CONTROL
16 D25 20WT/VT PCI BUS
DR8W-80 CONNECTOR PIN-OUTS 8W - 80 - 5

ENGINE COOLANT TEMPERATURE SENSOR (DIESEL)-2WAY
CAV CIRCUIT FUNCTION
A K914 18RD/WT SENSOR GROUND
A K914 18BR/WT SENSOR GROUND
B K2 18TN/BK ECT SIGNAL
B K2 18VT/OR ECT SIGNAL
ENGINE COOLANT TEMPERATURE SENSOR (GAS) - BLACK 2 WAY
CAV CIRCUIT FUNCTION
1 K900 18DB/DG SENSOR GROUND
2 K2 18VT/OR ECT SIGNAL
ENGINE OIL PRESSURE SWITCH-2WAY
CAV CIRCUIT FUNCTION
1 G6 18VT/GY OIL PRESSURE SIGNAL
2- -
EVAP/PURGE SOLENOID (NGC)-2WAY
CAV CIRCUIT FUNCTION
1 K52 18DB/WT EVAP PURGE CONTROL
2 K70 18DB/BR EVAP PURGE RETURN
DR8W-80 CONNECTOR PIN-OUTS 8W - 80 - 61

EVAPORATOR TEMPERATURE SENSOR-2WAY
CAV CIRCUIT FUNCTION
1 C121 20DB/DG SENSOR GROUND
2 C21 20DB/LG EVAPORATOR TEMPERATURE SENSOR SIGNAL
FENDER LAMP-FRONT LEFT (DUAL REAR WHEELS)-2WAY
CAV CIRCUIT FUNCTION
1 L7 18WT/YL FUSED PARK LAMP RELAY OUTPUT
2 Z947 18BK GROUND
FENDER LAMP-FRONT RIGHT (DUAL REAR WHEELS)-2WAY
CAV CIRCUIT FUNCTION
1 L70 18WT/YL FUSED PARK LAMP RELAY OUTPUT
2 Z948 18BK GROUND
FENDER LAMP-REAR LEFT (DUAL REAR WHEELS)-2WAY
CAV CIRCUIT FUNCTION
1 L7 18WT/YL FUSED PARK LAMP RELAY OUTPUT
2 Z947 18BK GROUND
FENDER LAMP-REAR RIGHT (DUAL REAR WHEELS)-2WAY
CAV CIRCUIT FUNCTION
1 L70 18WT/YL FUSED PARK LAMP RELAY OUTPUT
2 Z948 18BK GROUND
8W - 80 - 62 8W-80 CONNECTOR PIN-OUTSDR

POWERTRAIN CONTROL MODULE C3 (NGC) - WHITE 38 WAY
CAV CIRCUIT FUNCTION
1- -
2- -
3 K51 20BR/WT ASD RELAY CONTROL
4- -
5 V35 20VT/OR (4.7L) S/C VENT CONTROL
6 K173 18BR/VT CONDENSER FAN RELAY CONTROL
7 V32 20VT/YL (4.7L) S/C POWER SUPPLY
8 K106 18VT/LB NVLD SOLENOID CONTROL
9 K299 18BR/WT O2 1/2 HEATER CONTROL
10 K399 18BR/GY O2 2/2 HEATER CONTROL
11 C13 20LB/OR A/C CLUTCH RELAY CONTROL
12 V36 20VT/YL (4.7L) S/C VACUUM CONTROL
13 - -
14 V32 20VT/YL (5.7L) BRAKE SWITCH NO. 2 SIGNAL
15 V937 20VT/BR (5.7L) S/C SWITCH RETURN
16 K167 20BR/YL (5.7L) APPS NO. 1 RETURN
17 K400 20BR/VT (5.7L) APPS NO. 2 RETURN
18 V38 20VT/OR (5.7L) S/C SWITCH NO. 2 SIGNAL
19 K342 16BR/WT ASD RELAY OUTPUT
20 K52 18DB/WT EVAP PURGE CONTROL
21 T41 20YL/DB TRS T41 SENSE
22 G113 18VT PTO SWITCH SENSE
23 B29 20DG/WT BRAKE SWITCH SIGNAL
24 - -
25 K23 20BR/WT (5.7L) APPS NO. 1 SIGNAL
26 - -
27 - -
28 K342 16BR/WT ASD RELAY OUTPUT
29 K70 18DB/BR EVAP PURGE RETURN
30 K66 18DB/WT P/S SWITCH SIGNAL
31 - -
32 K25 18DB/VT BATT TEMP SIGNAL
33 N4 18DB/WT (3.7L/4.7L) FUEL LEVEL SENSOR SIGNAL
33 N4 20DB/WT (5.7L) FUEL LEVEL SENSOR SIGNAL
34 V37 20VT S/C SWITCH NO. 1 SIGNAL
35 K107 18VT/WT NVLD SWITCH SIGNAL
36 K29 20WT/BR (5.7L) APPS NO. 2 SIGNAL
37 K31 20BR FUEL PUMP RELAY CONTROL
38 T752 20DG/OR STARTER RELAY CONTROL
8W - 80 - 90 8W-80 CONNECTOR PIN-OUTSDR

CONNECTOR NAME/NUMBER COLOR LOCATION FIG.
Data Link Connector - Engine
(Diesel)BK Near T/O for Water In Fuel Sensor N/S
Dome Lamp BK Center of Headliner N/S
Door Ajar Switch-Driver (Base) BK Left Front Door 41
Door Ajar Switch-Left Rear (Base) BK Left Rear Door 43
Door Ajar Switch-Right Rear (Base) BK Right Rear Door 43
Door Lock Motor/Ajar Switch-Driver
(Except Base)BK Left Front Door 41
Door Lock Motor/Ajar Switch-Left
Rear (Except Base)BK Left Rear Door 43
Door Lock Motor/Ajar Switch-
PassengerBK Right Front Door 42
Door Lock Motor/Ajar Switch-Right
Rear (Except Base)BK Right Rear Door 43
Door Lock Switch-Passenger BL In Right Front Door 42
Driver Airbag Squib BK In Steering Column N/S
Driver Blend Door Actuator (Dual
Zone)BK Right Side of HVAC N/S
Driver Door Module C1 BL In Left Front Door 41
Driver Door Module C2 BL In Left Front Door 41
EGR Solenoid Right Front Engine 9
Electric Brake Provision Rear of Engine 22, 24
Engine Control Module C1 BK Left Engine 10
Engine Control Module C2 BK Left Engine 10
Engine Coolant Temperature
SensorBK Near Generator 6
Engine Oil Pressure Switch BK Lower Left Side of Engine 6, 9
Evap/Purge Solenoid BK Left Fender Side Shield 23, 25
Evaporator Temperature Sensor BK Right Side of HVAC N/S
Fog Lamp-Left WT Left Front Facia N/S
Fog Lamp-Right WT Right Front Facia N/S
Fuel Control Actuator (Diesel) BK Left Rear Engine N/S
Fuel Heater (Diesel) BK Left Side Engine 10
Fuel Injector No. 1 BK At Fuel Injector 6
Fuel Injector No. 2 BK At Fuel Injector 3
Fuel Injector No. 3 BK At Fuel Injector 6
Fuel Injector No. 4 BK At Fuel Injector 3
Fuel Injector No. 5 BK At Fuel Injector 6
Fuel Injector No. 6 BK At Fuel Injector 3
Fuel Injector No. 7 BK At Fuel Injector 6
Fuel Injector No. 8 BK At Fuel Injector 3
Fuel Pump Module LT GY At Fuel Tank 50
Fuel Pump Motor (Diesel) BK Left Side Engine 10
Generator BK Front of Engine 6, 9, 10
8W - 91 - 4 8W-91 CONNECTOR/GROUND/SPLICE LOCATIONDR
CONNECTOR/GROUND/SPLICE LOCATION (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
EXCESSIVE OIL CONSUMPTION OR
SPARK PLUGS OIL FOULED1. CCV System malfunction 1. (Refer to 25 - EMISSIONS
CONTROL/EVAPORATIVE
EMISSIONS - DESCRIPTION) for
correct operation
2. Defective valve stem seal(s) 2. Repair or replace seal(s)
3. Worn or broken piston rings 3. Hone cylinder bores. Install new
rings
4. Scuffed pistons/cylinder walls 4. Hone cylinder bores and replace
pistons as required
5. Carbon in oil control ring groove 5. Remove rings and de-carbon piston
6. Worn valve guides 6. Inspect/replace valve guides as
necessary
7. Piston rings fitted too tightly in
grooves7. Remove rings and check ring end
gap and side clearance. Replace if
necessary
STANDARD PROCEDURE
STANDARD PROCEDURE - REPAIR DAMAGED
OR WORN THREADS
CAUTION: Be sure that the tapped holes maintain
the original center line.
Damaged or worn threads can be repaired. Essen-
tially, this repair consists of:
²Drilling out worn or damaged threads.
²Tapping the hole with a special Heli-Coil Tap, or
equivalent.
²Installing an insert into the tapped hole to bring
the hole back to its original thread size.
STANDARD PROCEDUREÐHYDROSTATIC
LOCK
CAUTION: DO NOT use the starter motor to rotate
the crankshaft. Severe damage could occur.
When an engine is suspected of hydrostatic lock
(regardless of what caused the problem), follow the
steps below.
(1) Perform the Fuel Pressure Release Procedure
(Refer to 14 - FUEL SYSTEM/FUEL DELIVERY -
STANDARD PROCEDURE).
(2) Disconnect the negative cable(s) from the bat-
tery.
(3) Inspect air cleaner, induction system, and
intake manifold to ensure system is dry and clear of
foreign material.
(4) Place a shop towel around the spark plugs to
catch any fluid that may possibly be under pressure
in the cylinder head. Remove the spark plugs.(5) With all spark plugs removed, rotate the crank-
shaft using a breaker bar and socket.
(6) Identify the fluid in the cylinders (coolant, fuel,
oil, etc.).
(7) Be sure all fluid has been removed from the
cylinders.
(8) Repair engine or components as necessary to
prevent this problem from occurring again.
(9) Squirt a small amount of engine oil into the
cylinders to lubricate the walls. This will prevent
damage on restart.
(10) Install new spark plugs. Tighten the spark
plugs to 41 N´m (30 ft. lbs.) torque.
(11) Drain engine oil. Remove and discard the oil
filter.
(12) Install the drain plug. Tighten the plug to 34
N´m (25 ft. lbs.) torque.
(13) Install a new oil filter.
(14) Fill engine crankcase with the specified
amount and grade of oil. (Refer to LUBRICATION &
MAINTENANCE - SPECIFICATIONS).
(15) Connect the negative cable(s) to the battery.
(16) Start the engine and check for any leaks.
REMOVAL
(1) Perform the Fuel System Pressure Release pro-
cedure (Refer to 14 - FUEL SYSTEM/FUEL DELIV-
ERY - STANDARD PROCEDURE).
(2) Disconnect the battery negative cable.
(3) Remove the air cleaner resonator and duct
work as an assembly.
(4) Drain cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(5) Remove the accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
9 - 190 ENGINE - 5.7LDR
ENGINE - 5.7L (Continued)

þ Loss of engine power
þ Engine misfiring
þ Poor fuel economy
²Possible indications of the cylinder head gasket
leaking between a cylinder and an adjacent water
jacket are:
þ Engine overheating
þ Loss of coolant
þ Excessive steam (white smoke) emitting from
exhaust
þ Coolant foaming
CYLINDER-TO-CYLINDER LEAKAGE TEST
To determine if an engine cylinder head gasket is
leaking between adjacent cylinders, follow the proce-
dures in Cylinder Compression Pressure Test in this
section. An engine cylinder head gasket leaking
between adjacent cylinders will result in approxi-
mately a 50±70% reduction in compression pressure.
CYLINDER-TO-WATER JACKET LEAKAGE TEST
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING WITH COOLANT PRES-
SURE CAP REMOVED.
VISUAL TEST METHOD
With the engine cool, remove the coolant pressure
cap. Start the engine and allow it to warm up until
thermostat opens.
If a large combustion/compression pressure leak
exists, bubbles will be visible in the coolant.
COOLING SYSTEM TESTER METHOD
WARNING: WITH COOLING SYSTEM TESTER IN
PLACE, PRESSURE WILL BUILD UP FAST. EXCES-
SIVE PRESSURE BUILT UP, BY CONTINUOUS
ENGINE OPERATION, MUST BE RELEASED TO A
SAFE PRESSURE POINT. NEVER PERMIT PRES-
SURE TO EXCEED 138 kPa (20 psi).
Install Cooling System Tester 7700 or equivalent to
pressure cap neck. Start the engine and observe the
tester's pressure gauge. If gauge pulsates with every
power stroke of a cylinder a combustion pressure
leak is evident.
CHEMICAL TEST METHOD
Combustion leaks into the cooling system can also
be checked by using Bloc-Chek Kit C-3685-A or
equivalent. Perform test following the procedures
supplied with the tool kit.
REMOVAL
(1) Disconnect the battery negative cable.
(2) Drain cooling system.
(3) Remove the air cleaner resonator and duct
work.
(4) Remove the generator.
(5) Remove closed crankcase ventilation system.
(6) Disconnect the evaporation control system.
(7) Perform the Fuel System Pressure Release pro-
cedure (Refer to 14 - FUEL SYSTEM/FUEL DELIV-
ERY - STANDARD PROCEDURE). Disconnect the
fuel supply line (Refer to 14 - FUEL SYSTEM/FUEL
DELIVERY/QUICK CONNECT FITTING - STAN-
DARD PROCEDURE).
(8) Disconnect heater hoses.
(9) Remove cylinder head covers and gaskets.
(10) Remove intake manifold and throttle body as
an assembly.
(11) Remove rocker arm assemblies and push rods.
Identify to ensure installation in original locations.
(12) Remove the head bolts from each cylinder
head and remove cylinder heads. Discard the cylin-
der head gasket.
CLEANING
Clean all surfaces of cylinder block and cylinder
heads.
Clean cylinder block front and rear gasket surfaces
using a suitable solvent.
INSPECTION
(1) Inspect the cylinder head for out-of-flatness,
using a straightedge and a feeler gauge. If tolerances
exceed 0.0508 mm (0.002 in.) replace the cylinder
head.
(2) Inspect the valve seats for damage. Service the
valve seats as necessary.
(3) Inspect the valve guides for wear, cracks or
looseness. If either condition exist, replace the cylin-
der head.
(4) Inspect pushrods. Replace worn or bent push-
rods.
INSTALLATION
(1) Clean all surfaces of cylinder block and cylin-
der heads.
(2) Clean cylinder block front and rear gasket sur-
faces using a suitable solvent.
CAUTION: The head gaskets are not interchange-
able between left and right sides. They are marked
ªLº and ªRº to indicate left and right sides.
(3) Position new cylinder head gaskets onto the
cylinder block.
9 - 200 ENGINE - 5.7LDR
CYLINDER HEAD (Continued)

CAUTION: The head gaskets are marked ªTOPº to
indicate which side goes up.
(4) Position cylinder heads onto head gaskets and
cylinder block.
(5) Tighten the cylinder head bolts in three steps
(Fig. 4):
²Step 1Ð Snug tighten M12 cylinder head bolts,
in sequence, to 34 N´m (25 ft. lbs.) and M8 bolts to
20 N´m (15 ft. lbs.) torque.
²Step 2Ð Tighten M12 cylinder head bolts, in
sequence, to 54 N´m (40 ft. lbs.) and verify M8 bolts
to 20 N´m (15 ft. lbs.) torque..
²Step 3Ð Turn M12 cylinder head bolts, in
sequence, 90 degrees and tighten M8 bolts to 34 N´m
(25 ft. lbs.) torque.
(6) Install push rods and rocker arm assemblies in
their original position.
(7) Install the intake manifold and throttle body
assembly.
(8) If required, adjust spark plugs to specifications.
Install the plugs.
(9) Connect the heater hoses.
(10) Install the fuel supply line.
(11) Install the generator and drive belt.
(12) Install cylinder head covers(Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION).
(13) Connect the evaporation control system.
(14) Install the air cleaner.
(15) Fill cooling system.
(16) Connect the negative cable to the battery.
(17) Start engine check for leaks.CYLINDER HEAD COVER(S)
REMOVAL
(1) Disconnect battery negative cable.
(2) Disconnect coil on plug connectors.
CAUTION: The ground straps must be installed in
the same location as removed. The covers are
machined to accept the ground straps in those
locations only.
(3) Remove cylinder head cover retaining bolts,
and ground straps.
(4) Remove cylinder head cover.
NOTE: The gasket may be used again, provided no
cuts, tears, or deformation has occurred.
INSTALLATION
CAUTION: Do not use harsh cleaners to clean the
cylinder head covers. Severe damage to covers
may occur.
CAUTION: DO NOT allow other components includ-
ing the wire harness to rest on or against the
engine cylinder head cover. Prolonged contact with
other objects may wear a hole in the cylinder head
cover.
(1) Clean cylinder head cover and both sealing sur-
faces. Inspect and replace gasket as necessary.
(2)
Install cylinder head cover and hand start all fas-
teners. Verify that all double ended studs are in the cor-
rect location and install left and right ground straps.
CAUTION: The ground straps must be installed in
the same location as removed. The covers are
machined to accept the ground straps in those
locations only.
NOTE: The right hand ground strap is located on
the front inboard stud. The left hand ground strap
is located on the rear inboard stud.
(3) Tighten cylinder head cover bolts and double
ended studs to 8 N´m (70 in. lbs). Begin torque
sequence in the middle of head cover and torque
bolts moving outward in a crisscross pattern from top
to bottom.
(4) Install ignition coil on plug, and torque fasten-
ers to 12 N´m (105 in. lbs)
(5) Connect, ignition coil electrical connectors.
(6) Install PCV hose.
(7) Connect battery negative cable.
Fig. 4 CYLINDER HEAD TIGHTENING SEQUENCE
DRENGINE - 5.7L 9 - 201
CYLINDER HEAD (Continued)