So I got stuck on the side of the Autobahn friday night with the same condition as before, P2112 & P2111 codes for stuck TB causing limp mode. I opened the actuator motor on the side of the road to find more gunk and corrosion had worked its way loose and was once again causing the motor to stick. It also turns out in hind sight that I rushed the first cleaning, (as evidenced by the ever persistent gunk), and in an effort to drive home from work set the return spring with two counter clockwise turns to get the blade to return to the closed position. It turns out that this should not have been needed and was indeed another indicator that the actuator was still dirty. This also means the actuator motor had to work twice as hard to open the TB...so only one counter clockwise turn of the return spring until the keys fit into their proper place should be used. if the TB is functioning properly this should be more than enough to return to the closed position.
SO, I once again removed and disassembled it, cleaned the whole thing again with alcohol wipes to start. I ended up filling the motor stator housing with lemon juice to dissolve any rust, as well as the return spring, I filled a shot glass with lemon juice and submerged it. Let it sit for a couple of hours (2-3), then pour it out into a bowl some chunks of rust came out with it and then brushed vigorously with a nylon brush. Cleaned out with alky wipes along the way and dried out with paper towel looking to see if more rust and gunk came out on the paper, it did, so I soaked it in lemon juice again for 2 more hours. Repeated these steps until the stator housing looked like new inside. Wiped with alky wipes one last time and let sit to dry. Lightly coated the entire interior with grease, (Vaseline), once dry as well as filled the brass bearing at the bottom with grease to ensure smooth operation.
After cleaning all the gearing off, I greased them ALL, on all sides with grease, and shoved some grease down into the pit behind the main gear which connects directly to the blade shaft in an attempt to plug it and catch some meth/water, most likely a futile attempt.
The motor itself was cleaned pretty well the first time i did it. I just cleaned it off real good with the alcohol wipes, but, since I couldn't separate the motor from the housing, I couldn't clean the contractors correctly, so I ended up plugging up the holes on the other side with grease and then filling the pit where the contactors and springs reside with rubbing alcohol and turned the motor vigorously. Once i did that for a min or 2 I dumped the alcohol onto a napkin and found that I had indeed worked some carbon loose. I did this 2 more times until I did not get carbon in the alcohol anymore. I coated the motor itself, (the portion that spins with the windings), with a thin coat of grease to prevent further corrosion.
Once all this cleaning and greasing was done, I test fit and moved the assembly by hand and it feel MUCH better. The thing with the gear grease is it will pick up other dirt and grim as you work them so keep an eye on them and glean the dirty grease out and re-grease them until you dont dirty up the grease anymore. Also dont leave to much in there, remove the excess grease as you check it, extra grease is no good.
Once I was happy with the cleaning/greasing, I added some extra gasket to the stator housing seal by cutting out the side of a styrofoam cup and tracing out the outer edge of the mounting location. Cut an interior hole for the motor to slip thru, holes for the 4 screws and used it along with the stock gasket to increase seal with the housing. I hope this will lessen the ability for boost to work into there and out the sides. The stock gasket here is very thin rubber and also sits into a recess, which I think lessens its effectiveness.
In hind sight I should have taken some pictures but I forgot, had hands full of grease and dirt, lazy blah blah blah excuses. I can take some later if anyone needs them.
I really need to find out how I lost the cap that is supposed to cover the return spring adjustment access. This missing cap is most likely the reason for this issue in the first place, as it allows boost to leak through the TB with little resistance and it brings the meth/water with it.
I hope this write up helps someone in the future if they start pulling P2112/P2111 codes and getting stuck in limp mode. This problem has the potential to leave you stranded so...enjoy.