Mercedes C63s M177 Tuning ( Catless DP )

[hpttestguy]

Hello, I recently bought a 2018 C63s ( W205 Pre-Facelift ), I ordered some Aftermarket DPs and got them fitted by a mechanic.

I'd like to get into the tuning world so I spent the last 2 weeks reading up on this, I've ordered a MPVI2 and it will arrive soon.

Symptoms:
- pops and burbles on decel ( running lean )
- overly smelly exhaust ( running lean, i understand that cat-less DPs will have a bad smell but i think its overly smelly )

So far here are my assumptions:
- My car is running lean
- This is harmful for my engine
- I need a tune to lower the AFR ratio

So my question is, to get rid of my car being too lean, is the only thing required to do is decrease the AFR ratio?

[chevota]

I think you need to use the HP scanner to see whats happening first. I doubt youre lean but we'll see. No clue about the smell but it shouldnt be any worse than pre cat car. I can make mine richer so I assume you can

[Schnell]

This sounds more like a slightly rich condition than lean. The smell and some popping aren't abnormal with catless DPs. Unless it's severe.