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.

Good luck.

__________________
Paul S.

2001 E430, Bourdeaux Red, Oyster interior.
79,200 miles.

1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".