ok guys - hoping someone out there can help... (kinda long, but wanted to be sure all the details were out there)
Already had this happen once - even posted in here about it - http://www.seomoz.org/q/client-s-site-dropped-completely-for-all-keywords-but-not-brand-name-not-manual-penalty-help
Guy was a brand new client, all we did was tweak title tags and add a bit of content to his site since most was generic boilerplate text... started on our KW research and competitor research...
in just a week, from title tag and content tweaks alone, he went from ranking on page 4-5 to ranking on page 3-4... then as we sat down to really optimize his site... POOF - he was gone from the Googs...
He only showed up in "site:" searches and for exact matches of his business name - everything else was gone.
Posted in here and on WMT - had several people check it out, both local guys and people from here (thanks to John Doherty for trying!) - but no one could figure out any reason why it would have happened.
We submitted a reconsideration request, explaining that we knew we hadn't violated any quality guidelines, that he had less than 10 backlinks so it couldn't be bad linking, and that we had hardly touched the site. They sent back a canned response a week later that said there was no manual penalty and that we should "check our content" - mysteriously, the site started to show back up in the SERPs that morning (we got the canned response in the afternoon)
There WAS an issue with NAP mismatch on some citations, but we fixed that, and that shouldn't have contributed to complete disappearance anyway.
SO - the site was back, and back at its page 3 or 4 position... we decided to leave it alone for a few days just to be sure we didn't do anything... and then just 6 days later, when we were sitting down to fully optimize the site - POOF - completely gone again.
We do SEO for a lot of different car dealers all over the country, and i know our strategies work. Looking at the competition in his market, he should easily be ranked page 2 or 3 with the very minimal tweaking we did...
AND, since we didn't change anything since he came back, it makes even less sense that he was visible for a week and then gone again.
So, mozzers... Anybody got any ideas? I'm really at a loss here - it makes zero sense that he's completely gone, except for his biz name... if nothing else, he should be ranking for "used cars canton"...
Definitely appreciate any help anyone can offer -