my 97 E420 has an intermittent wobbly idle issue and someone suggested that there could be an air leak somewhere, and I could replace all rubber parts in the PCV system. I'm a newbie and I'm not sure what parts consist of the PCV system, can someone provide a complete list of parts I need to buy? Also, has anyone ever posted a DIY-guide for this? Finally, how much $ in parts are we looking at?

I'm also told it'd be wise to replace the rubber seals on the air intake.. what is the part # for this?

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Current cars:
2001 MB E55 AMG
2003 Honda S2000
2000 Honda CRV

Gone but not forgotten:
2004 BMW 325i 5sp sport
1999 BMW 540i sport
1997 MB E420
1995 BMW M3 coupe