2006 Mercedes-Benz C-Class - pricey intake manifold?

the dealer wanted to replace the intake manifold for 2200 on a c230 with 133178 miles. is the normal price to replace

Without knowing where you are and why the intake manifold needs replaced it is difficult to say the price is normal. Any good independent shop should be able to do this so get a couple of estimates .

You have just discovered the high cost of European luxury vehicles.

If you are located in the U.S. a remanufactured intake manifold is $900, plus gaskets, seals etc. Labor is 3.2 hours. For the price you were quoted was there any additional work?

they are in the 400 range online

I would still like to know WHY the intake manifold supposedly need to get replaced

I can think of a few reasons, but I’d like to hear it from OP

Being out of warranty, I would just find a reputable independent shop and save a lot of money.