mAMG

Hi all,

My SL55 had one of the ABC hoses changed, and it required a lot of work to be changed (engine lifted, etc).

After that, I hear a flutter sound from low rpm increases/accelerates when rpm increases, it disappears at higher rpm due to engine noise I guess. Mechanic said its normal because he had to repair on of the abc hoses.

Now, I've installed Mid-length header, and the sound is even louder now ! So apparently its something not installed back or fitted probably after the abc work is done.

Any idea what could that be ?

Thanks.

kbob999

Exhaust leak? By messing with the exhaust, it got worse.
I'd spend some time with the car on a lift and track it down.

mAMG

nope no leaks. It is coming from the driver side. Is there any way it is ABC related ? The ABC pump is making hissing/air escape sound all the time when the car is stationary.

The flutter sound appeared after abc work performed, that had to lift the engine and remove something in steering to change those abc hoses. the sound is clear appears only under load.

mAMG

You are right. I took the car today to another garage, they checked and they found a leak at the headers gasket and the downpipes.

We ordered new oem gasket for the eurocharged headers, but we couldn't find a replacement for the faulty downpipe gasket. They have applied glue to the downpipe gasket and reinstalled it.

Sound now is decreased a lot ... Hopefully a new downpipe gasket eliminate it.

pjw1967

Watch out for carbon monoxide in your engine room. Can easily build up at idle and get pulled into the cockpit if exhaust system isn't 100% tight.