I was at about 150k when it started, am at exactly 168k when I started tearing it apart a few weeks ago. I ran a few bottles of BG 44k through the fuel system when this first started, used the CRC GDI Intake cleaner stuff, pretty much tried everything cheap before getting a leak-down test to confirm my worst suspicions. This went on for over a year before I decided to fix it properly. The shop that did the leak-down quoted me 7k to do this job.How many miles do you have on the engine? I had a very small shake at idle (No CEL, no misfires) but it has since gone away. I'm running a few bottles of Sea Foam through my fuel system and might do the intake version as well... but having a valve stick sucks... I'm at 94k miles.