Throttle Body Actuator 7/70 Issue

[Joe8]

Hello All,

Looking for some feedback on my situation.

2008 M3 Coupe
69,600 miles
Throttle Body Actuator Bank 1 replaced ~ 48k miles

Jan 6: Limp Mode with a buffet of dash warnings we all see. Called BMW dealer for appt w/ loaner. Loaner avail Feb 16. Appt set.

Jan 9: Took to independent shop for cautionary reasons and they pulled faults #2B16 (throttle body actuator bank 2) and #2B59 (thermostat). Called BMW dealer to inform them.

Independent shop did not clear codes and drove in limp mode for 2 weeks just putting to work and back (12 miles total/day) The ~3 weeks prior to Feb 16 appointment, the codes and "engine service" light disappeared and car ran fine and no codes.

Feb 16: After a few days, BMW Dealer can't "reproduce" the codes and is unable to cover replacing the throttle body actuator under California's 7/70 emissions warranty. Dealer did replace the thermostat without question. (Odd they'd do that without a code for it). I gave them permission to have a tech "drive it" to reproduce the code. No luck. Now they are throwing in the towel and apologizing.

I spoke to the service manager and was unable to get it replaced. Called BMW USA Customer Relations and they took a complaint but wouldn't replace. The rep Ian was really not understanding. Just said "sorry if we can't reproduce the code, we can't replace it."

The independent shop even emailed the diagnosis, date, time, mileage, codes pulled, etc to the dealer.

It's obviously an issue that will surface and throw the codes sometime in the near future.

Any advice? Suggestions on how I could approach it? Doesn't the ECUs retain all the historic data that would show that was an issue?