If you still have the injectors out how about running a compression check again, and do it both "dry" and "wet" to see if a little oil on the rings improves it any. I am suspicious of your compression gauge since you showed a decrease in compression after adjusting #4 valves so I would say run them all again and this time, if possible, have the gauge be closer to normal temperature (keep it in your coat to keep it warm). Maybe it has a leak when it gets cold...wouldn't be the first time something cold contracts enough to give a faulty reading.

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Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz