4.3 doing repetitious TQMGNT spark retard at cruise

[8up]

I just finished building a 4.3, lunati 270 cam, 10.5:1 flat tops, marine intake, heads -.020, total rebuild, and getting my tune down pat, and im back to MAF, and doing some logging to track spark. I've noticed that every so often, 15 seconds or so, the TQ MGNT spark advance pulls anywhere from -13 to -18 degrees timing from the engine. Happens with foot feed, and cruise control. Im lost as to why it would do this, the graph on the spark advance looks like a heartbeat monitor on flat highway with cruise set at 65 Mph........ stumped.

2002 sonoma. 4.3 auto.

[5FDP]

Post the tune and logs, maybe something can be changed.

[8up]

Here is the log file from this morning and the tune file its running. Sorry, i know i should have posted them the first thing, 7:32AM to 7:36AM

[5FDP]

I'm not totally sure what is causing it. You could try maxing out the Torque mngt VS RPM table too on the engine side, I would try that anyway.

[Russ K]

Zero the A/C Torque>Max Retard table.

Russ Kemp