2 Attachment(s)
'15 Ram 1500 I can't figure this one out.
Earlier this year I installed ARH long tubes, and a 6.4 Power Wagon intake manifold and 6.4 injectors. I've gotten the injectors scaled to a close setup for now. I replaced both upstream o2s with new and added a wideband about the same time. A nameless remote tuner "tuned" the truck, which equated to just power enrichment tweaks, so tuning has been left to me apparently. I drove the truck around for a while, but after a couple months, CEL started illuminating with P0300(random misfire detected), and idle in PN is erratic. tach needle bounces almost as if idle destabilizes for some reason. Replaced plugs with new thinking it might have been time for that. Noticed an exhaust leak, so I replaced the gaskets with new, and retorqued shortly after as prescribed. Looking at the O2 readings on the logs, It looked like I might have o2 issues again. Replaced sensors again. Still showing weird readings, but identical to before, so the sensors weren't fouled. Began to think maybe a vacuum leak. Used a vacuum gauge, and found about 20-21 psi, and needle just barely twitching. Nothing there. Thinking along the vacuum leak lines, I pulled the intake back off, and found cylinder 7 and 8 o-rings slightly damaged. Replaced all with new. I have a Scat Pack Charger, so I tried swapping throttle bodies to see if throttle might be the issue with no change. Map sensor was installed new with intake, and appears to seal properly. At this point, I'm kind of stuck, thinking that maybe an o2 sensor has damaged wiring, causing a weird reading, or maybe some sort of cam issue, or pushrods maybe. No evidence of a head gasket, or valve issue, but I'm about at wit's end at this point. Here is a copy of the tune, and my latest log. During normal operation, the truck only has this weird idle in Park and Neutral, but you can see the tach bouncing 2-300 rpms on normal cruising. Maybe I'm completely glossing over some glaring issue because of inexperience. The log is the entire operation from initial startup after the intake gasket repair, to warm-up, to driving, and even a WOT pull. At the end is a small idle portion where the spark drops out entirely, and the engine nearly stalls. It should stand out to any of you willing to take the time to check it out.
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Attachment 106366
