I was wanting to know how often would a bad IP hydraulic head and rotor be the culprit of black smoke in a 1.6 NA?
Facts:
glow plugs: 7 sec.
timing: 1.0mm
T-stat: 192 F
Injectors: 155 bar, re-manufactured Bosch
Head gasket: composite with ARP studs @ 85 ft. lbs.
Maybe the pump need some fuel injector cleaner run through it or something. I just can't think of anything else that could cause any soot. You can't see it all that well in the rear view mirror during the day, but at night with someone's headlights behind you, it looks like you're transporting Cheech and Chong.
Standard operating procedure for vw diesel most any mechanical for that matter. Headlights will make the slightest haze look worse.