03 lope

Hey was wondering if anyone could help me out. I have an 03 cummins w/ afe intake and afe blade runner GT turbo. My truck has been loping on and off for over a month now, if I put it in gear it’s smooth(Auto) if I turn the ac on it’s smooth compressor kicks off it lopes kicks back on it’s smooth. Also lopes when decelerating if there’s no load. No smoke ? great mileage took a 10k lb 5 horse trailer to globe and back to see if injectors were needing to be cleaned that didn’t change anything. Also no change with tuner hooked up or not. Only thing I’ve replaced is the FCA with no change. Idle is steady @800 even when it lopes. Any help is appreciated. Has NO CEL or codes hooked to snap on scanner. Cleaned a whole bunch of sensors and connections last weekend.

TIA

What tuner is on the truck? If it's custom tuning I'd look at the PID data for the main duration. If the duration drops below like 200-high 100s it doesn't fire the injectors. Pretty much the ECM saying that it's useless to fire at that low of a duration. Had it happen on my truck when messing around with different tuning files. Bumped up the duration a little bit and the lope at idle stopped.

Sent from my SAMSUNG-SM-G930A using Tapatalk