I don't think it would hurt to run a few tankfulls with Techron in it back-to-back-to-back.
I don't know if it'll cure the problem, or not, if it is a sticking valve.
There are a good number of members here that are in Nor. Cal.
Try the search function in the "good shops" sub-forum and see what comes up.
Sticking valve issues have come up for discussion from time-to-time, too. If you experiment with the search function, some of the good threads might come up.
2001 E430, Bourdeaux Red, Oyster interior.
1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".