New to the forum and first time posting, but to start I am a Expert Level Audi Certified Tech at a dealer so no need to worry about misleading or confusing statements but I'm at a loss of options.
I have a 2000 S4 that only misfires in Cylinder 1 ONLY at idle, P0301 Cyl 1 Misfire Detected Intermittent ONLY CODE, on average 20-40 misfires per min at idle, but when cruising, WOT, or off idle all goes to 0 misfires. I have swapped in new coil packs, new OEM "pink top" fuel injectors, new intake manifold gaskets, swapped ICM's, swapped ECM's, checked mechanical timing, checked cam adjusters/tensioners, checked timing gear to cam (sometimes the "D" profile of the camshaft to cam gear can get rounded but it is flush), compression tested all cylinders 205-215 PSI, cylinder leakage test 5%, running compression test 60 psi all cylinders, vacuum gauge at idle for entire engine 20" hg and steady with no fluctuations, checked every vacuum line/hoses/check valves for leaks, fuel pressure at idle is 50PSI (specs something like 40-60 or so don't remember exact but I know its ok), swapped in new fuel pressure regulator, checked ECM harness for any chafing on bulkhead studs, checked resistance of coil connectors and fuel injector connectors, used boroscope to check for carbon - none anywhere, checked cams for worn lobes, checked lifters and valve springs. The f hose is silicone and new, the crankcase breather system is new (spider hose assembly new), tried a capacitive discharge but still no change. Car is 100% stock. I've completely run out of options, my thoughts are an extremely small burnt area of a valve or extremely slight bent valve or a sticky/notchy valve guide? Any other input/sugguestions appreciated.