RawBenz

I thought mine was pinging but i think it might be the exhaust.

At low revs during 1st if i hold the throttle at about 3-4000rpm i can hear like a brrrrrr (marbles in a can)

With my old car it was completely catless which ran into a muffler and i had the same sound and everyone said it was just the exhaust because it was catless.

L8brker

Ahh it's says min 93 on my gas flap therefore I put in 94 oct available at every chevron in Canada , I don't know what you Americans use because it will ping on 91 period then the knock sensors retard timing and reduce power .
I went to Seattle 6 months ago , got shell gold and it pinged like a mother

2012C63AMG

My state max is 91 octane with 10% ethanol unless you buy race gas I along with everyone else in my state have no pinging issues, I know plenty of people who drive more tuned cars and yes our gas is probably the lowest quality in the US under the guise of environmental I can assure you things don't ping. Ill be happy to use 87 gas with 10% ethanol all week if you would like.

As I was told by a tuner my 91 octane probably loses me 5% on hp compared to states with better gas which can be tuned to take use of that gas.

Critter

Personally would not use Shell gold gas to start a bon fire, it might ping too.
Lets get back to the issue though, just how does a computer controlled engine "ping " when there is a knock sensor incorporated into the system to retard the timing and stop engine failure. Of course using the factory setup or "tune" never heard or felt "ping" on a distributer-less engine.

Ingenieur

my Audi RS4 with 12.5:1 Cr ran fine on 91
the Cr of the C63 is much lower (11.3:1) so 91 should be fine

the engine has controls that retard timing to limit knock

the 93 is the euro RON/ROZ rating, not the (RON + MON)/2
they recommend 98 but you can run a minimum of 93 RON/ROZ

the US manual says 91 (RON + MON)/2

98 RON ~ 93-94 (RON + MON)/2
93 RON ~ 89 (RON + MON)/2

91 is fine

bdbmotorsports

Spark plug heat range to high. Pull a plug, if you post a good picture I can tell you if that is it but bet you need to drop heat range 2 points. They run a pretty hot plug, good for quick warm up but bad when you advance the timing.

adv4nced53

Has the car thrown a code? If not, you're not hearing detonation. I seriously doubt your ear is as good as a knock sensor lol

If you're convinced you're detonating:
1] go back to stock tune and see if it helps
2] check spark plugs
3] check air filters
4] check injectors

At part throttle, it's usually a fuel starvation issue.

RawBenz

What does pinging actually sound like? Anyone have a video/audio?

I was told it's like marbles in a can, so when i'm at part throttle holding it... it sounds like marbles in a can (could it be exhaust?)

I have an aftermarket tune from Evotech Germany.

Ingenieur

sounds like 'rattling'

if you are under heavy load and hear it, as you ease off it should fade away

Critter

Drive up a hill at about 25mph as you get into the incline press the throttle down a little to increase speed but not allow the car to drop a gear, this will cause a non computerized car to ping if the timing is too far advanced. I find it hard to believe you guys are hearing actual engine ping and as stated above there is a knock detector to combat this. Now aftermarket tune all bets are off.

RawBenz

I never hear mine on heavy load.. only when i apply the throttle slowly i can hear a gurgle like marbles.. but i think it could be my exhaust as it's catless.

Critter

Exhaust flowing through headers or a flow through setup, without cats will produce a "tinny" sound when using stainless pipes, maybe more noticeable with aftermarket stainless thin wall pipe. IMO