I inherited a 98 Ram 5.9 after the previous owner tried changing the distributor cap and ran into problems that snowballed into bigger ones (destroyed distributor base, moved distributor out of timing).

To make a long story short I bought and installed a new distributor (first one I seen without a drive gear on it). I installed it in exactly the same spot as the old one and would now like to manually time the engine.

Where is the connector or pigtail located that I would have to disconnect before setting timing? The engine is at TDC, and the rotor isn’t pointing at the number one firing piston (3 o’clock from # 1 piston. Thanks in advance for your help.

 

That has to be set with a scan tool. It controls the injectors. not the ignition timing. Ign. timing is controlled by the computor.

 

Charlie1935, thanks for the fast reply. It was my understanding that there is a pig tail that goes into a wiring harness or the firewall that can be disconnected to set the timing manually with a timing light.

Just so I understand you correctly, what you’re saying is that even if the distributor has been disturbed from its original position while the engine was off, the computer will then reset the timing on its own after starting the engine?

If that’s correct I would then need a scan tool to set the injectors? Would you please explain the steps in the scanning procedures along with where I could find a scanning tool?

 

All I know is that they are expensive. Probably have to go a dealer or a up to date independant garage.

 

You gotta have the dealer set the sync signal with a DRB scan tool.... It's the only way I know of!

 

Thanks for the replies. I did a little more research and I found the answer.
The only thing the distributor does now is supply spark of course, but it has a cam sensor inside that controls injector timing. When the #1 cylinder is at TDC the rotor should be facing about 1 o’clock position. After this is achieved, there is a notch in the distributor housing that needs to be lined up with the rotor. This is called "indexing" the distributor.

 

Is it supposed to run at that point???

 

Yes, it places it within range, then if it needs any additional adjustments the ECM sets it from there.

 

DISTRIBUTORS—3.9/5.2/5.9L ENGINES
REMOVAL
CAUTION: Base ignition timing is not adjustable on
any engine. Distributors do not have built in centrifugal
or vacuum assisted advance. Base ignition
timing and timing advance are controlled by the
Powertrain Control Module (PCM). Because a conventional
timing light can not be used to adjust distributor
position after installation, note position of
distributor before removal.
(1) Remove air cleaner assembly.
(2) Disconnect negative cable from battery.
(3) Remove distributor cap from distributor (two
screws).
(4) Mark the position of distributor housing in
relationship to engine or dash panel. This is done to
aid in installation.
Fig. 42 Distributor Pre-position
1 – 1 O’CLOCK POSITION
2 – BASE SLOT
3 – DISTRIBUTOR BASE
Fig. 43 Distributor Engaged Position—2.5L
4-Cylinder Engine
1 – DISTRIBUTOR BASE SLOT
2 – CLAMP BOLT MOUNTING HOLE (ON ENGINE)
3 – DISTRIBUTOR BASE
AN IGNITION SYSTEM 8D - 21
REMOVAL AND INSTALLATION (Continued)
(5) Before distributor is removed, the number one
cylinder must be brought to the Top Dead Center
(TDC) firing position.
(6) Attach a socket to the Crankshaft Vibration
Damper mounting bolt.
(7) Slowly rotate engine clockwise, as viewed from
front, until indicating mark on crankshaft vibration
damper is aligned to 0 degree (TDC) mark on timing
chain cover (Fig. 44).
(8) The distributor rotor should now be aligned to
the CYL. NO. 1 alignment mark (stamped) into the
camshaft position sensor (Fig. 45). If not, rotate the
crankshaft through another complete 360 degree
turn. Note the position of the number one cylinder
spark plug cable (on the cap) in relation to rotor.
Rotor should now be aligned to this position.
(9) Disconnect camshaft position sensor wiring
harness from main engine wiring harness.
(10) Remove distributor rotor from distributor
shaft.
(11) Remove distributor holddown clamp bolt and
clamp (Fig. 46). Remove distributor from vehicle.
CAUTION: Do not crank engine with distributor
removed. Distributor/crankshaft relationship will be
lost.
INSTALLATION
If engine has been cranked while distributor is
removed, establish the relationship between distributor
shaft and number one piston position as follows:
Rotate crankshaft in a clockwise direction, as
viewed from front, until number one cylinder piston
is at top of compression stroke (compression should
be felt on finger with number one spark plug
removed). Then continue to slowly rotate engine
clockwise until indicating mark (Fig. 44) is aligned to
0 degree (TDC) mark on timing chain cover.
(1) Clean top of cylinder block for a good seal
between distributor base and block.
(2) Lightly oil the rubber o-ring seal on the distributor
housing.
(3) Install rotor to distributor shaft.
(4) Position distributor into engine to its original
position. Engage tongue of distributor shaft with slot
Fig. 44 Damper-To-Cover Alignment Marks—Typical
1 – ALIGNMENT MARK
2 – TIMING CHAIN COVER MARKS
3 – CRANKSHAFT VIBRATION DAMPER
Fig. 45 Rotor Alignment Mark—3.9/5.2/5.9L Engines
1 – CAMSHAFT POSITION SENSOR ALIGNMENT MARK
2 – ROTOR
3 – DISTRIBUTOR
Fig. 46 Distributor Holddown Clamp—3.9/5.2/5.9L
Engines
1 – CLAMP BOLT
2 – HOLDDOWN CLAMP
3 – DISTRIBUTOR HOUSING
8D - 22 IGNITION SYSTEM AN
REMOVAL AND INSTALLATION (Continued)
in distributor oil pump drive gear. Position rotor to
the number one spark plug cable position.
(5) Install distributor holddown clamp and clamp
bolt. Do not tighten bolt at this time.
(6) Rotate the distributor housing until rotor is
aligned to CYL. NO. 1 alignment mark on the camshaft
position sensor (Fig. 45).
(7) Tighten clamp holddown bolt (Fig. 46) to 22.5
N·m (200 in. lbs.) torque.
(8) Connect camshaft position sensor wiring harness
to main engine harness.
(9) Install distributor cap. Tighten mounting
screws.
(10) Refer to the following, Checking Distributor
Position.
CHECKING DISTRIBUTOR POSITION
To verify correct distributor rotational position, the
DRB scan tool must be used.
WARNING: WHEN PERFORMING THE FOLLOWING
TEST, THE ENGINE WILL BE RUNNING. BE CAREFUL
NOT TO STAND IN LINE WITH THE FAN
BLADES OR FAN BELT. DO NOT WEAR LOOSE
CLOTHING.
(1) Connect DRB scan tool to data link connector.
The data link connector is located in passenger compartment,
below and to left of steering column.
(2) Gain access to SET SYNC screen on DRB.
(3) Follow directions on DRB screen and start
engine. Bring to operating temperature (engine must
be in “closed loop” mode).
(4) With engine running at idle speed, the words
IN RANGE should appear on screen along with 0°.
This indicates correct distributor position.
(5) If a plus (+) or a minus (-) is displayed next to
degree number, and/or the degree displayed is not
zero, loosen but do not remove distributor holddown
clamp bolt. Rotate distributor until IN RANGE
appears on screen. Continue to rotate distributor
until achieving as close to 0° as possible. After
adjustment, tighten clamp bolt to 22.5 N·m (200 in.
lbs.) torque.
The degree scale on SET SYNC screen of DRB is
referring to fuel synchronization only. It is not
referring to ignition timing. Because of this, do
not attempt to adjust ignition timing using this
method. Rotating distributor will have no effect on
ignition timing. All ignition timing values are controlled
by powertrain control module (PCM).
After testing, install air cleaner assembly.