Dodge R1500 1999 Service Manual page 164

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
D - ADJUSTMENTS - CNG & GASOLINE
1999 Dodge Pickup R1500