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New PMD still Problems...

The IP flange is what bolts up to the timing cover like Bison said, there is a wedge on the timing cover, and thats where I drew the lines on the picture, on the edge of the flange and the wedge tip. If the IP is towards passenger side of the wedge tip then youll have a positive TDCO, and if its towards the drivers side you should have a negative TDCO value, and it shouldnt be very far off of the wedge tip.

When you unplugged the IAT did you observe the IAT value on the scanner go cold? And no change in fuel rate or timing?

And what did you observe for fuel rate and timing with ECT unplugged.

The PCM may not be your problem, but I have found that the trucks dont like sitting down at 5 cam degrees advance at idle. Some even are at 4.5 degrees. Whereas later GM programming has them at 9-11 degrees at idle. I find my IP starts to hunt for the timing when I program it for less than 7 degrees, and at the same RPM fuel rates need to be higher.
 
Multiple problems your vehicle,

1. Desired idle- 638 RPM Ok
2. Engine Speed-600-619-638 Ok
3. Actual IP Timing-26.84-27.37 DEG Bad This is actually OK, this is the physical position of the IP in CRANK degrees
4. Desired Injection Timing-5 DEG Bad This is OK too, beased on early GM programming
5. Measured Injection Timing-4.8-4.9 DEG Bad This is the value that has to match the desired and its close so this is OK
For data on 4 & 5 is that in time set mode ??? if not you have big issues as 3 and 4 should match when out of time set in time set mode desired should be 0 with 3.5 deg average
6. TDCO Offset- 0.35 DEG within GM spec -.25 to -.75 if that is a negative value
7. Fuel Rate(at normal warm idle)- 18.12-18.44 (NO SPUTTER) on high side for idle with warmed up engine
8. BARO- 13.61 PSI
9. Intake Air Temp- 166.2F High for an idle IAT
10. Fuel Calibration- 130COUNTS What is this I have never seen this before?This is the resistor value, which I think is a #7 resistor
11. Injection Pulse Width- 2.02-2.06 Creeping to limit we recommend looking for a new IP
12. Cam Reference Missed- 0 COUNTS
13. Crank Reference Missed-0 COUNTS
14. ENGINE TEMP AFTER IDLE 15 MIN (with no airlfow) 204.4 you probably have stat-rad-or fan clutch issues

Otherwise I agree with you that there are a couple problems.
 
What scan tool is being used I forgot to ask that as the timing readings I'm flagging as bad don't match what I've seen on T2/MT2500 are OBD-Is displaying the timing readings differently than the OBD-IIs do ?

That resistor count is that a OBD-I function also? or something unique to type of scan tool used?
 
The IP flange is what bolts up to the timing cover like Bison said, there is a wedge on the timing cover, and thats where I drew the lines on the picture, on the edge of the flange and the wedge tip. If the IP is towards passenger side of the wedge tip then youll have a positive TDCO, and if its towards the drivers side you should have a negative TDCO value, and it shouldnt be very far off of the wedge tip.

When you unplugged the IAT did you observe the IAT value on the scanner go cold? And no change in fuel rate or timing?

And what did you observe for fuel rate and timing with ECT unplugged.

The PCM may not be your problem, but I have found that the trucks dont like sitting down at 5 cam degrees advance at idle. Some even are at 4.5 degrees. Whereas later GM programming has them at 9-11 degrees at idle. I find my IP starts to hunt for the timing when I program it for less than 7 degrees, and at the same RPM fuel rates need to be higher.
On the IAT the scanning did go cold -37.5 to be exact. plugged it back in and it read 111F. I did not check the fuel rate. will do that tomorrow when i get off work.

Truck will be parked the rest of the week and ill have to drive work powerjoke furd. Ill do my best and get all the readings again and maybe the tuning software. Thanks again for your guys help. hopefully i can get her back to normal soon
 
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