I have 2.2 in my GLHT that was rebuilt 20k miles ago. We melted #1 piston, which dropped the compression from 125 to 90. We threw in new pistons and rings, and I have 10-15 easy miles on it since getting it back together. Compression is now 118-125-125-125 (was 125x4 before meltdown). I expect the 118 is due to some unusual/eneven glazing I noticed where #1 melted. The thing smokes like wild now though, mostly grey, tint of blue sometimes. It smokes pretty well constantly; far, far worse than it did with the melted piston. There is what appears to be oil in the tailpipe as well. There is no blow-by either. I can only assume this relates to the oil control rings or expander? Anyone run into this before? I am going to try hammering on it to see if they seat, but wanted to see if anyone else has been down this road. I've never had a rebuild smoke before!
I originally thought it must be the turbo, but we replaced it with what was believed to be a good one (worked when I removed it). There is no oil in the turbo hoses or intercooler. I even disconnected the oil feed to the turbo (blocked the turbine also) and dropped the downpipe, and still it smokes, so not the turbo I guess! I poked at the stem seals and the are still soft and appear to be well seated. PCV is stock TII airbox and plumbing.