Retarded Timing?

My 2003 gti has a stage 2 ecu, and an open downpipe to straight pipe. When i start it cold it dies after sounding like misfire or running on like 2 cylinders unless i give it gas but sometimes that doesnt work. after a pull it will stall in neutral. also when idling after its warm the rmps drop like 200-300 every few seconds. it runs rich and white smoke which im pretty sure is unburnt fuel comes out the tailpipe on startup especially. there is definitely power loss too. im pretty sure this is a timing issue because the engine makes a ticking sound. Ive replaced the intake gasket, exhaust manifold gasket, the turbo to exhaust manifold gasket, the downpipe gasket, the valve cover gasket, the spark plug hole gasket, the half moon seal, the cam chain tensioner gasket. i put a rkx DV on it and the problems seemed to start after that, but ive tried adjusting the DV and i tried putting the stock one back on but the problem seemed to be worse with the stock one back on. I retourqed the knock sensor to 15 ft/lbs. My next move is probably the crankshaft position sensor. I took the turbo off and brought it to a turbo shop and the guy said the turbo is fine. the only code i get is po172. Any help is appreciated! :heart: