after blogger import, unwanted replacement of text with code

I imported my posts from Blogger to WP using the import script (and S. additional comment import) – worked fine. Strange enough, parts of posts are striked through, but they weren’t before. It’s not in the WP database though. An example: https://www.iroke.de/wp/?p=95
Hmm, no wait, looking at the code at IE it tells me, there’s a <del>… where the strike starts, I have a “-10%” in the text. Could it be that some plugin looks at the entry and interprets the minus as the <del> tag?
Possible culprits from my plugins list:
PreFormatted 2.0-rc1 Jerome Lavigne
Text Control 2.0b1 Jeff Minard
X-Valid 0.98 Jamie Talbot