mbrown_btx

newdude, thanks for the information! What are your suggestions for moving forward? Do I need to tear it apart again and replace the parts that I didn't the first time around? Not preferred but neither is a large car payment...

newdude, thanks for the information! What are your suggestions for moving forward? Do I need to tear it apart again and replace the parts that I didn't the first time

newdude, thanks! What are your suggestions for moving forward? Do I need to tear it apart again?

Thank you for the reply! I did not replace the lifter trays as the engine mechanic I spoke to suggested reusing the old ones rather than replace them with a non-OEM version that would be available. I did not mess at all with the VLOM, I was actually guided to disable the AFM all-together as it seems to cause more issues than it helps. Additionally, I have a basic code reader that will also read some engine parameters but not all of them. I plan to replace the oil pressure sensor filter and maybe the sensor this weekend hoping that is the key issue. If not, where is the pump assembly located in the event that is the next move?

I drive a 2012 GMC Yukon XL (Denali Version) with the 6.2L engine (with AFM technology still intact) that has 205,000 miles on it. I recently experienced the DOD lifter failure on cylinder 4 (passenger side second valve back) and subsequently replaced all of the lifters on that side only. While I had the head pulled for the lifter replacement, I had it resurfaced and checked for proper operation by a local engine machine shop which I used to get the lifters (instead of buying cheap Chinese lifters from O'Reilly's). After re-assembly of everything there is still a ticking noise (assumed lifter noise) coming from the passenger side. I have checked all rocker arms and push rods for issues and ensured each was re-torqued properly and there was no excess play following re-installation, ticking still exists. During all of these efforts post initial re-assembly I have noticed the fuel pressure after the engine warms up is much lower than normal (less than 20psi while idling), there is an occasional miss, I am experiencing low speed loss of power, and very rough down shifting of the transmission. After reading some posts on this forum I believe I need to replace the oil pressure sensor filter and hopefully that will resolve most of these issues but wanted to post and see if anyone had any other suggestions. I like this truck and want to keep it running as long as possible given it is paid off. Thank you in advance for your reply!