i had the same thing happen. Plumber had to snake it out all the way to the street. It wasn't to expensive. No problems since! If Mark can't do it, call All About plumbing. 248 542-7850. I got them from the St A's bulletin. I was happy with them.
ISO plumber in Washington Twp. area. Toilets are all bubbling! Husbands thinks it's the vent and is currently getting a snake. Any recommendations if we end up needing someone is appreciated!
Jim W. replied:
We use All About Plumbing and have been happy with them: 248-542-7850. Good luck.