I removed the intake manifold last night from my C280 to gain access to the EGR tube to fix an egr low flow problem, during the process the (crank case?) Breather Hose (Part# 1040943582) cracked in 3 places and was very brittle. I made a makeshift hose from 1/2" hose although the original was 3/4" hose. Now after removing and cleaning the EGR tube and putting everything back together the engine idles rough below 800 RPM, it sometimes drops to about 500rpm then catches it. Anything above 800/1000 RPM its smooth as silk. I'm wondering if the engine needs to re-learn its gas mixture at idle now that it has a completely clean EGR tube, or is it possible if the breather hose being a different diameter in any way can effect vacuum in turn effecting idle? Also, I had the dealership clean the EGR tube about 2 years ago, but when I removed it last night it was caked solid at the end. However 2 years ago I did replace the EGR valve and switch over valve, and although the engine is idling rough it has not thrown any codes to turn on the check engine light. Sorry for the long post, I just wanted to give all the details. If anyone has any suggestions please let me know.

Thank you and have a Happy Thanksgiving!

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1986 190E 186K (For Sale)
(Maroon, Tan leather)
1996 C280 Sport 208K
(Brilliant Silver, Black Leather)
2002 CLK430 Sport 45K
(Brilliant Silver, Gray Leather , Birdseye Maple)