i jus bought a mercedes 500sel and the gas mileage was very bad i didnt know the problem so i left it alone and yesterday i took off the air filter housing and it was filled with sand and dirt and the air filters were shot and black,so i cleaned it out and bought new air filters and the gas mileage is so much better but now when i start it the idle bounces around 5 and 10 and when im stopped at a red light,also there is a loud sucking sound when i open the hood and now the whole engine sounds different

You forgot to reconnect the hose that goes from the bottom of the air filter housing to the valve cover, didn't you?

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A.S.E Tech A1,A6,A7,A8 & MVAC 609 + EPA 608

Unless stated otherwise, any question I ask is about my greymarket 1985 380SEL.

maybe but i dont remember pulling out any hose from the bottom housing i will look tmrw,will there be any harm done because i forgot to do that?

Not really, just your idle problem...

Could be that it's just so loose that you don't feel it slip out when you take the air box off.

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A.S.E Tech A1,A6,A7,A8 & MVAC 609 + EPA 608

Unless stated otherwise, any question I ask is about my greymarket 1985 380SEL.

o thanks alot its to late to check right now but tmrw morning i will,where is the hose located u are talkin about,any pics