Hi & Welcome to the site.
Unfortunately 2.2 HDi's are far less common in 406 saloons & estates, only 800 or so were ever registered in the UK. There's been a recent 'surge' in the number of 2.2 owners on the forum, but that's from 2 or 3, up to perhaps 10 - 12 today & that total includes a few coupes.
Having said that, I'd say this is a more 'hands on' forum.
I don't think there's a specific 'howto' for the 2.2, but this guide for an HDi 90 is a very good starting place.
viewtopic.php?f=10&t=8229
I did the same job on my 2.2 about 6 weeks ago and can verify it's almost identical on our engines. The one critical difference is the camshaft locking holes are at the 4 o-clock position on a 2.2, not 8 o-clock as on the 2.0 engines. Other than that it's the same job.
When undoing the crank pulley retaining bolt, I borrowed two long extension bars, so I could comfortably tug on the breaker bar from beside the car, makes it much easier. I also had the Haynes book to refer to throughout and it does help.
On mine, I changed the belt kit, (belt, tensioner & idler) plus aux belt, tensioner & idler - felt like a bit of overkill, but mine's pushing 160k and was last done at 72, so I figured it's worth it.
Any questions, just let us know.
