Originally Posted by
Jack G
I am not certain about the differences beween the R121 and R171. I buy my xfire parts from FCP (Foriegn Car Parts.com) in the US. They donot have any listings for our xfires but they will respond to models like SLK320 R121 etc. I have purchased engine & auto transmission parts from them for my 2005 xfire roadster limited which has the 3.2L engine.

Arrrggggg, this is what I get when I try to remember specifications from memory (71 yrs young and going quickly)! I tried your search and got even more confused because the AI and webpages bring up stuff when the searches match to (and mismatches to) any one of the search terms. I am certain of the actual reason your search brings up the webpage you referenced, and why I got it wrong as well.
1.
Chrysler Crossfire - Wikipedia
2.
Mercedes-Benz SLK-Class (R170) - Wikipedia
3.
Mercedes-Benz M112 engine - Wikipedia (E32 version is mentioned in the this link listing the crossfire)
Try to search the MB 171 engine, none. Try to reference the MB R120 or the R171 engine, nothing. Try to search other search criteria with various MB and SLK search terms with the things that don't match like R170 or R121 or R171 (the mix-up from results are amazing).
Note: MB and Chrysler had a bad divorce, so MB doesn't recognize the Crossfire much hence the limited info in it's Wiki..
Anyway, I found out I was wrong, and I found out how you got to FPC euro (webpage or.AI searching) while using search engines.
The 170 and 171 classes are the platform designations.
Oh, the engine in the SLK-320 and the crossfire is the M112 MB engine. I am glad I researched this so I can re-learn wth I have myself mixed up (LOL). Hope this helped you, it def helped me!
By the way, I just found out here the Launch CRP123 and the CRP123E does NOT read the SRS modules in the 2007 & 2008 Crossfires, I purchased these two trying to reset/diagnose the SRS light on my dash for why is it lit (airbag light). So many readers are not reading the Crossfire (I guess at least the 07 & 08) that it is very frustrating to have good information (these care are an enigma).
Take care!, and have fun maintaining your 05 soft top!
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