Now that's what I call a well written question: all pertinent info laid out in chronological order.

Anyway, there's a good chance you did thin out the oil. I would change it as a next step. It's easy and inexpensive and you'll stop wondering about it. If you want, you can put the end of the dipstick to your nose and see if you smell any gasoline in the oil, but sometimes that's iffy. After the oil change, drive for a bit and see if the smoke situation improves.

Also, make sure none of your spark plugs got fuel-fouled when you ran rich. You say it runs smooth, but it doesn't hurt to check (well ok, it is kinda PITA to remove and look at the plugs...) When a plug is fuel-fouled, it doesn't fire because there's a coating of unburnt hydrocarbons on the electrode.

Erwin 89 750iL Lowered (a little)

Mouse over for details >>> Engine/Driveline Wolf engine and throttle chips 19 lb, 4-hole (Design 3) fuel injectors PowerFlow Intake Air Filter Kit Custom Cold Air Boxes Royal Purple 20W-50 3.64 LSD w/Royal Purple gear lube Royal Purple trans fluid Interior Phone removed, replaced with cut-to-length dash wood trim on hinge E38 Shifter Knob, Console Plate, and Boot M-Tech 2 M-technic Steering Wheel - air bag deleted E38 Self-Dimming Mirror Interior Light Fading Module (Shogun special) Audio BMW Business CD Player "CD43" Head Unit Refurbished factory amp w/equalizer Bass blockers (300hz/4ohm) on stock front kick panel speakers Rear deck speakers: Alpine SPS-13C2 5.25" 2 way 175 Watt with bass blockers Subwoofers: 2 JBL GTO804 8" 4-ohm subs Subwoofer install: custom sealed enclosure mounted behind ski bag opening Subwoofer amp: Alpine MRP-M450 400w MONO CD changer relocated to driver's door bottom pocket, actuated by bio- mechanical arm controlled by semi-intelligent nut behind the wheel Suspension H&R Lowering Springs (1/2 coil removed from fronts) Koni adjustable front shocks Stock rear shocks (self leveling) Racing Dynamics Stress Bar Stock front sway bar Dinan rear sway bar - 21mm M5 aluminum lower control arms Front tires: 245-40-18 Goodyear Eagle F1 GS-D3 on 8.5" EuroTech rims Rear tires: 275-40-18 Michelin Pilot Sport PS1 on 9.5" EuroTech rims Exterior/Body 25% Side tint, 5% Rear tint BMW Mud flaps - rears trimmed to tire width Rear fender lips rolled Smoked side markers (after pic taken) Euro Smiley Headlights (after pic taken) Soft close trunk retrofit E66 trunk emblem "750 iL" (after pic taken) Zymol wax Way too many paint chips touched up Brakes Front Rotors: 850CSi, 324 X 30 mm, cross-drilled and slotted Rear Rotors: stock size, cross-drilled and slotted Pads: Hawk Performance Ceramic (may switch to HPS) Stainless steel lines Racing Blue brake fluid

• How to screw things up..... (pic) - eliasazem 2008-07-09 13:29:31 (372 views)
  • I have the same problem..... - mcf 2008-07-28 10:29:23 (57 views)
  • whoooo hell yeah whats your trick for making the engine look so good!!! (nt) - beach911 2008-07-10 00:21:08 (83 views)
    • I want to know that also (nt) - steinway 2008-07-10 11:16:52 (69 views)
      • I had chromed all bolts, clamps and whatever I got my hands on.. (url) - eliasazem 2008-07-10 17:01:41 (111 views)
        • www.flickr.com/photos/bimmer_750 (nt) - eliasazem 2008-07-10 17:32:32 (108 views)
          • that looks exquisite - steinway 2008-07-11 05:44:18 (60 views)
            • left the engine in it's place and removed some parts...look (pic) - eliasazem 2008-07-11 08:33:10 (159 views)
              • what's that in the trunk at the right? - steinway 2008-07-11 13:58:28 (62 views)
                • Looks like a storage compartment where the 2nd battery usually is at with a 750 (nt) - Johan750 2008-07-11 17:53:13 (64 views)
                  • Never heard of a second battery usually in a 750..... (nt) - eliasazem 2008-07-11 18:04:23 (61 views)
                    • so have you looked what's behind it? - steinway 2008-07-12 02:55:51 (52 views)
                    • It's not big enough....do you have a pic to show me...thankx (nt) - eliasazem 2008-07-11 18:05:29 (53 views)
                      • all Highline for example have a 2nd battery (url) - shogun 2008-07-11 23:14:41 (90 views)
  • Change the oil - erwin 2008-07-09 14:40:45 (91 views)
  • Rings probably OK - Patrick C 88 750 160K 2008-07-09 14:09:05 (92 views)
    • i was burning oil at same rate 400mi/qt - ridgelyrocket 2008-07-10 21:19:08 (68 views)
    • Patrick is right. - alv12 2008-07-10 11:36:44 (69 views)
      • Re: bring banks in sync - steve209 2008-07-10 14:03:42 (86 views)