1999 5.9L Fuel Sync

I have a customer with a 1999 B Van with a 5.9. We're having issues getting the fuel synchronization set. I have an Autel scanner that can do the Set Synchronization routine, and I can see the degrees.

The setting keeps bouncing around, usually a ten degree range. -2 to +8 for example. It also fairly regularly spikes to +23 degrees. I can get the distributor close, but it never sets into one place. If I rev the engine to 1000RPM the degrees freeze on my scanner and won't update until I let the RPMs come down again and restart the routine.

The customer replaced the timing change thinking that it was too slack and allowing the cam to bounce, but that didn't change anything. New aftermarket cam sensor in the distributor. New crank sensor. He did file down the crank tone ring because the previous crank sensor was set too tight and boogered it up a little. His other mechanic said it looked fine after filing, and I can see a steady RPM graph on my scanner. I took out the distributor and checked it for wear, there's no play in the shaft and the drive gear in the block looks okay. I'm not sure if it's properly timed to no. 1 cylinder TDC though.

Any ideas?

From the 2001 Ram Service Manual:
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.

Hmm. I think I tried to set it while it the engine was hot, but can't remember now. It idles like a top fueler, wants to die all the time. After my customer did the chain we didn't run it long, he hadn't put the radiator back in at that time.

Correct synching procedure needs to be performed, but there was a TSB out about the distributor/oil pump drive gear bushing having excessive wear.

So check it! Don't go by the marking because the outer ring on the balencer because it may have moved. Check you are on TDC #1 cylinder on the COMPRESSION STROKE Then set the distributor like this...

That just gets it in the ball park so it will run. Signal needs to be correctly set with a scan tool.

got a feeling this is the van on fb. all he did was put and intake on it. wont start and backs up against the starter bad. several people have made suggestions, even my dad. dad even looked in the fsm for the procedure to sync without drb. finally someone posted the tsb that dealers used to use to hand sync the dist using a volt meter.

The car is currently at my customer's house. This is some side work for me and a project car for him. I'll check it next time we get together. The distributor rotor did line up with that notch when the balancer was at TDC, though.


That is one of my theories, since the timing jumps around so much. The motor is a reman, not sure who built it. Who knows if they replaced the bushing or properly reamed it with the correct tool. Do you have the TSB number?

Thanks for all the responses, it's given me some avenues to explore.

You sure you're not 180 out of time?

tsb 18-16-92

Apparently that's normal(?) in the OBD2 controlled Magnums.
Read the last couple pages of this thread: https://board.moparts.org/ubbthread...43375/10/super-duper-mpg-318-part-2.html

Actually what i posted is in the service manual, With a new timing chain it should work fine.

Not on OBD2.

if this is the man on fb, he says he got it running great. i felt that he used the tsb to get it running correctly from all indications he gave.

Yes OBD2. The pic is in there also that's where it came from.

That will get you close. Have you ever set a sync signal with a scan tool?

It's not the ignition timing that's jumping, it's the fuel sync timing.

I told my customer about the distributor drive gear and bushing, and how there's a TSB for it wearing too much. I also found a bunch of related forum threads throughout the internet with the same symptoms and they point to the bushing. I don't know if my customer is going to replace it, haven't heard back from him. I kinda want to do it just to see if it fixes the problem.

Thanks for all the help, guys.