TeraPatrick

Hi Everyone,

Ever since I got a burble tune there's been a weird ticking noise on idle (please see the attached video) in my muffler. I always thought that my primary cat blew and the noise were pieces from the honey comb. I had a secondary cat delete so it's definitely not that. So recently I installed catless downpipes to hopefully solve this problem and nope it still ticks. They took out the original downpipes and the primary cats look almost new. Iv'e had the exhaust replaced because of the weird rattling noise a lot of people were having and they replaced it under warranty. I am now tuned with downpipes, so taking it to the dealer isn't exactly the best solution. To describe the sound, its like there's 3 or more mexican jumping beans bouncing around in my muffler.

srO_Michael_Orz

sounds like misfiring.

Ksun_w205

Is it only during cold start or always at idle?

TeraPatrick

It happens on idle. I think it's the spark plugs since I haven't changed them since the tune. I have no check engine light on.

TeraPatrick

Update*

It could be a loose heat shield or bolt in the muffler. If it was the spark plugs I would of heard ticking from the engine. I'm taking it to a shop on Saturday to figure out what that damn noise is.

Ksun_w205

Those are what I thought as well but it definitely does not sound like misfire to me. Also another thing it really sounds like is my previous car (w204 C300) when I did a resonator delete it also made the sound exactly like yours but only on cold starts and it was little bits of un-burnt fuel popping in exhaust. Not sure if it applies to you but just what I experienced. Please keep us updated! I'm thinking about getting DP and tune also but i heard so many people having little issues with their cars.

TeraPatrick

Quick Update:

Went to a tuner shop yesterday to see if the mufflers were loose causing it to rattle. Turns out it was my exhaust flaps the whole damn time. I find it weird though because my friends have the same car with the same tune with catless downpipes and their flaps don't make this noise. I'm going to bring in my car dealer and hopefully they don't flag it since it has a tune.

untamedd

these exhaust flaps are garbage and it baffles me that mercedes has failed to address this known issue. i had it changed and the damn thing started rattling again. got rid of all the flaps now and can drive in peace

amg8

I want to chime in and say I was also having intermittent issues with my exhaust flaps. Although it is not a noise issue but it sometimes won't open. This in turn also caused an error code in the system. To remedy this, I went straight pipe -- problem solved.

Encore818

I'm suffering from a rattling flap as well but it only comes when the engine is under load.

I have a secondary cat delete on my car. Would they even look and try to fix it seeing as I've messed with the factory exhaust?

I feel like it would be the perfect excuse for the dealer to avoid fixing it.

untamedd

i was in the same situation as you and the dealer refused to even look at the exhaust to diagnose the issue.

tried to talk some sense in to them by trying to explain that a secondary cat delete has nothing to do with the valves but obv they wouldnt budge.

go to any exhaust shop and have them weld the valve permanently shut and plug in a simulator.

FLC63s

Cat deletes and DP's typically get noted and "flag" depending on your SA.. if you have a GREAT relationship with your SA and or Dealer, they might over look it..

To assume they will not look over the whole car, when its in, is not good.. they will do a FULL over on the car..

TeraPatrick

I was in the same boat as you 9 months ago. They don't care as long as your'e honest and tell them.

TeraPatrick

I'm in good relationship with my SA and Mechanic at the dealer and today they told me to bring it in. They told me it won't get flagged unless we need to plug in the OBD, but if that's the case I can just not have them fix my muffler issue which isn't the end of the world.

Ksun_w205

Does the flaps only apply to the performance exhaust or all exhausts?

mbjj57

the performance exhaust is on all the gts, gtc, gtr series . not sure about the c series
If there is an exhaust valve button on the center console it means you have the "flaps".

Ksun_w205

Oh yes I got that, but the center console button only controls the valves in the muffler. I was wondering if the flaps that make the noise is from the muffler or the valved H pipe? I believe all C63 comes with Valved h pipe