1999 DODGE RAM engine

VALVES. Connect 2 hoses with shutoff valves to manifold gauge set
center port. Connect one hose to vacuum pump and other hose to
refrigerant container. Weight of refrigerant container before and
after charging can be used to determine amount of refrigerant drawn
into system. Using vacuum pump, purge air from center hoses.
3) Fully open manifold gauge set low-side valve and
refrigerant container valve to allow refrigerant to enter A/C system.
When no more refrigerant is being drawn into A/C system, start engine
and allow to idle. Select MAX A/C, set blower motor speed to maximum
and allow remaining refrigerant to be drawn into A/C system.
NOTE: When ambient air temperature is high, it may be necessary to
use an external cooling fan to blow air through condenser and
radiator.
4) When proper amount of refrigerant has been added, close
refrigerant container valve. Allow any refrigerant remaining in hose
to be drawn into A/C system. When low-side pressure decreases to about
30 psi (2.1 kg/cm
), close center valve on manifold gauge set. Ensure
A/C system is operating properly. Disconnect manifold gauge set.
Install service port caps. Check system for leaks. See LEAK TESTING.
GENERAL MOTORS
Manufacturer recommends using A/C Refrigerant Recovery,
Recycling And Recharging (ACR4) System (J-39500). The ACR4 system ha\
s
one filtering cycle during recovery plus an automatic multiple pass
filtering during evacuation cycle. Follow manufacturer's instructions
provided with ACR4 equipment being used.
JEEP
Connect recovery/recycling equipment, meeting SAE standard
J1991 or J2210, to vehicle. Charge A/C system to specifications, using
equipment manufacturer's instructions.
LEAK TESTING
TYPES OF LEAK DETECTORS
Bubble Solution Detector
This is a solution applied externally at suspected leak
points. Leaking refrigerant will cause the detector to form bubbles
and foam. A soap and water solution also works well.
Dye Solution
This is a colored solution that may be introduced into the
A/C system. The dye will show up and color components at leak points.
Some manufacturers offer refrigerant containing a Red dye. This dye-
containing refrigerant is installed by normal charging procedures.
Other dye solutions are visible with a Black light only.
Electronic Leak Detector
This instrument will draw in any leaking refrigerant through
a test probe, and then sound an audible signal or create a flashing
light if refrigerant is found. It is the most sensitive of the leak
detectors used. Leak detectors are sensitive to windshield washing
solutions, many solvents and cleaners, and some adhesives. Ensure
surfaces near test areas are clean and dry to prevent false signal or
detector damage. Liquids ingested into detector will damage detector.
See Fig. 24 .

Fig. 24: Electronic Leak Detector
PREPARATION FOR LEAK TESTING
Connect manifold gauge set to air conditioning system. Ensure
low-side and high-side gauge set valves are closed. Check system
pressure. It should be at least 50 psi (3.5 kg/cm
). If system is
empty, evacuate A/C system and apply 28 in. Hg of vacuum. If system
holds vacuum for 15 minutes there most likely are no leaks present. If
low, add just enough refrigerant (about 10 ounces) to bring system to
50 psi (3.5 kg/cm
).
Ensure all joints, connections, and fittings are free of oil
dirt and other contaminants. Using a refrigerant leak detector, check
all refrigerant line connections for leaks. Check condenser and
compressor seal area.
Start engine and allow to idle. Operate A/C system for about
5 minutes. Set A/C controls to outside air, and high blower speed.
Turn A/C on, and open vehicle windows. Turn engine off and wait 2-7
minutes. Refrigerant is heavier than air. Always check for leaks at
bottom of refrigerant lines and components. Refrigerant oil will leak
with refrigerant. Visually check all connections and compressor clutch
area for oil stains. If compressor shaft seal is leaking, a fresh oil
streak will normally be seen on underside of hood, above compressor
clutch.
Always perform leak testing after A/C service. Move
refrigerant leak detector slowly to check for leaks, as leaks will not

be detected if leak testing is performed too quickly.
BUBBLE DETECTOR LEAK TESTING PROCEDURE
This leak detection method is recommended when it is
impossible or difficult to determine the exact location of the leak
using other methods. Although commercial bubble detectors are more
effective, household soap solutions may be used.
Using the dauber that comes with the commercial soap
solution, apply the solution to all joints, connections, fittings or
controls where a leak might be suspected. If high-suds household
solutions are used, apply them with a small brush. Wherever bubbles
form, leaks are present and must be repaired. check the entire system
as there may be more than one leak.
ELECTRONIC LEAK TESTING PROCEDURE
NOTE: Some electronic leak detectors will function on only R-12
systems or on only R-134a systems, and some will function on
both R-12 and R-134a systems. Familiarize yourself with the
tester being used and know what type of system you are leak
testing.
Electronic leak detectors should be used in well ventilated
areas. Avoid using them around explosive gases. Always follow
manufacturer's instructions for the specific tester being used. If
none are available, proceed as follows:
1) Turn all controls and detector sensitivity knob to OFF
position or zero setting. Connect leak detector to an approved source
of power. Turn switch ON, and allow unit to warm up for approximately
5 minutes.
2) Check operation of tester by positioning probe in a
reference source where refrigerant is known to be present in small
amounts. Adjust controls and sensitivity knob until detector reacts
properly. Move probe away from refrigerant source and the reaction
should stop. If it continues, adjust the sensitivity knob to a lower
setting.
3) When tester reacts properly, leak test air conditioning
system by moving probe UNDER all components, fittings and connections.
Keep the probe moving. To check evaporator insert probe into drain
tube opening or a heater duct. DO NOT allow probe to contact
refrigerant or refrigerant oil. When leaks are found, repair them as
necessary. Keep in mind that there may be more than one leak.
DYE SOLUTION LEAK TESTING PROCEDURES
CAUTION: Dye-charged refrigerant cans are available to be used as
internal leak detectors. The use of this type of solution may
void some manufacturer's warranties. Be sure to check with
the A/C system manufacturer concerning the use of dye-charged
leak detectors. Dyes which work in R-12 systems will not work
in R-134a systems.
The following procedure is for introducing a dye solution,
not dye-charged refrigerant, into A/C system.
1) Connect manifold gauge set to air conditioning system in a
normal manner. Remove center hose from manifold gauge set, and replace
it with a short piece (6" long) of 1/4" tubing using two 1/4" flare
nuts. Connect a container of dye solution to the tubing.
2) Connect one end of gauge set center hose to dye solution
container. Connect a container of refrigerant to the other end of the
hose. Operate engine at idle speed. Set the air conditioning system
for maximum cooling. Slowly open the low-side hand valve to allow the


D - A D JU STM EN TS - C NG & G ASO LIN E

1999 D odge P ic ku p R 1500
1999 ENGINE PERFORMANCE
CHRY - On-Vehicle Adjustments - Trucks & RWD Vans - CNG & Gas
Dakota, Durango, Ram Pickup, Ram Van, Ram Wagon
ENGINE MECHANICAL
Before performing any on-vehicle adjustments to fuel or
ignition systems, ensure engine mechanical condition is okay.
VALVE CLEARANCE
NOTE: All engines use hydraulic lifters. No adjustments are
required.
IGNITION TIMING
On all models, ignition timing is controlled by Powertrain
Control Module (PCM). Ignition timing is nonadjustable. DO NOT attempt\
to adjust ignition timing by rotating distributor.
NOTE: On Dakota 3.9L, 5.2L and 5.9L, Durango, Ram Pickup, Ram Van
and Ram Wagon, if distributor is rotated, fuel system
synchronization will be changed. If distributor is removed or
rotated, check fuel system synchronization. See procedures
under FUEL SYSTEM SYNCHRONIZATION under FUEL SYSTEM.
FUEL SYSTEM
FUEL SYSTEM SYNCHRONIZATION
NOTE: Fuel system synchronization is controlled by position of the
distributor. Rotating distributor WILL NOT change ignition
timing, but will change fuel system synchronization. Fuel
system synchronization should be checked anytime distributor
is removed or rotated.
Dakota 3.9L, 5.2L & 5.9L, Durango, Ram Pickup, Ram Van & Ram
Wagon
1) Connect scan tool to Data Link Connector (DLC). DLC is
located below driver's side of instrument panel, near steering column.
See Fig. 1 , 2 or 3.
2) Using scan tool manufacturer's instructions, access SET
SYNC display on scan tool. Following scan tool displays, start engine.
Warm engine to normal operating temperature. Vehicle must be in closed
loop. With engine idling, if scan tool displays IN RANGE along with
0
, this indicates correct distributor location. The degree reading
displayed on scan tool indicates the fuel synchronization, not
ignition timing.
3) If scan tool display is correct, shut engine off. Remove
scan tool. If scan tool does not display IN RANGE along with 0
, go to
next step.
4) If scan tool displays a plus (+) or minus (-) sign next\
to
the degree number, and/or the degree number displayed is not zero,
loosen but DO NOT remove distributor hold-down bolt.
5) Rotate distributor until scan tool displays IN RANGE.
Continue to rotate distributor until a reading as close as possible to

0 is obtained. Tighten distributor hold-down bolt to 16 ft. lbs. (22
N.m). Shut engine off. Remove scan tool.
Fig. 1: Locating Data Link Connector (DLC) (Dakota & Durango)
Courtesy of Courtesy of Chrysler Corp.
Fig. 2: Locating Data Link Connector (DLC) (Ram Pickup)
Courtesy of Courtesy of Chrysler Corp.

Fig. 3: Locating Data Link Connector (DLC) (Ram Van & Ram Wagon)
Courtesy of Courtesy of Chrysler Corp.
IDLE SPEED & MIXTURE
Idle speed and mixture are controlled by Powertrain Control
Module (PCM). No adjustment is required. PCM controls Idle Air Control\
(IAC) motor for proper idle speed. See SELF-DIAGNOSTICS - JEEP, TRUCKS\
& RWD VANS article for diagnosis of incorrect idle speed or IAC motor
operation.
THROTTLE BODY MINIMUM AIRFLOW
NOTE: Throttle body minimum airflow procedure checks throttle body
calibration for correct idle speed. Procedure may be used for
idle speed problems caused by the throttle body. Throttle
body minimum airflow procedure should be performed after all
other diagnostic procedures have failed to produce results
that indicate a throttle body related problem. Ensure IAC
motor is operating correctly before performing this
procedure.
Dakota, Durango, Ram Pickup, Ram Van & Ram Wagon
1) Start engine and warm engine to normal operating
temperature. Ensure all accessories are off. Shut engine off. Remove
air duct at throttle body.

2) Disconnect vacuum line at PCV valve located in valve
cover. Install .185" fixed orifice Air Metering Fitting (6714) into
disconnected vacuum line in place of PCV valve.
3) Disconnect purge vacuum hose from passenger's side front
corner of throttle body, next to MAP sensor. Place cap on vacuum hose
fitting on throttle body.
4) Connect scan tool to Data Link Connector (DLC) located
below driver's side of instrument panel, near steering column. See
Fig. 1, 2 or 3.
5) Start engine and warm engine to normal operating
temperature. Using scan tool manufacturer's instructions, select
SYSTEM TEST and then access the MINIMUM AIRFLOW display on scan tool.
When accessed, scan tool will count down to stabilize idle RPM and
display minimum airflow idle RPM. Minimum airflow idle RPM should be
500-900 RPM.
6) Shut engine off. If minimum airflow idle RPM is correct,
throttle body is okay. Go to next step. If minimum airflow idle RPM is
not within specification, using approved cleaner, clean throttle body
and recheck minimum airflow idle RPM. If correct minimum airflow idle
RPM cannot be obtained, replace throttle body. Go to next step.
7) Remove air metering fitting. Reinstall vacuum hoses as
necessary. Reinstall air duct on throttle body. Remove scan tool.
Ram Pickup 8.0L
Throttle body minimum airflow cannot be checked on this
application.
THROTTLE POSITION SENSOR
NOTE: Throttle Position (TP) sensor is nonadjustable. Use following\
procedure to check TP sensor calibration. For complete
testing of TP sensor and wiring circuit, see SELF-DIAGNOSTICS
- JEEP, TRUCKS & RWD VANS article.
Dakota, Ram Pickup, Ram Van & Ram Wagon
1) Remove components for access to electrical connector at TP
sensor mounted on throttle body. With electrical connector installed
on TP sensor, turn ignition on with engine off. DO NOT start engine.
2) Using digital volt-ohmmeter, measure voltage at center
terminal on electrical connector for TP sensor with throttle valve
closed (idle position). Voltage should be greater than .35 volt, but
less than .90 volt.
3) Slowly open throttle to full throttle and note voltage
reading. Voltage should smoothly increase to less than 4.50 volts.
Replace TP sensor if voltage is not within specification.


D - A D JU STM EN TS - D IE SEL

1999 D odge P ic ku p R 1500
1999 ENGINE PERFORMANCE
CHRY - On-Vehicle Adjustments - Trucks - Diesel
Ram Pickup
ENGINE MECHANICAL
Before performing any on-vehicle adjustments to fuel system,
ensure engine mechanical condition is okay.
VALVE CLEARANCE
NOTE: Valve clearance must be adjusted with engine temperature less
than 140F (60C).
1) Disconnect negative battery cables. Remove valve cover.
Remove fuel pump gear access cover, located at front of engine. Using
Engine Barring Tool (7471B), rotate engine to align pump gear mark
with TDC mark on gear housing cover. See Fig. 1.
Fig. 1: Rotating Engine
Courtesy of Chrysler Corp.
2) With cylinder No. 1 at TDC, check valve clearance on
proper valves. Perform STEP 1. See Fig. 2. See VALVE CLEARANCE