ms_

Hi,

Recently just traded in my A45 AMG for a C63 coupe with p31 pack and let me say i absolutely love it and do not regret leaving the A class.

One thing which is bothering me is on slight acceleration, say from take off until around 3500RPM ( then motor becomes louder masking the sound ) there is a sight ticking noise which is only apparent on acceleration. Ticking noise is not apparent when slowing down to a stop or even free reving in neutral.

I also notice a slight miss-fire when idling, which i can feel through the steering wheel, or maybe this is normal with a v8 firing order? Not sure..

Any help would be great!

Thanks in advance.

Ingenieur

engine check light?
any codes?
if not I would say no issues

ms_

No engine light (yet), is there a way to check for stored fault codes??

Moe

Ingenieur

You need a scan tool

Maybe stale gas
Run the tank low and top off with good feash fuel
See if that helps

If it was misfiring, ping'ing or detonating you would get a light

ms_

Hmm okay..

I have had several tanks of fuel through it, using 98+ octane ( in Australia, it's the top stuff at the pump ).

I will book it into the dealer and see how we go! Thanks for the input

Rolf de Graaff

Does the ticking come from the rear?
I have a P30 which also ticks under light acceleration, I thought maybe it had to do something with engaging/disengaging of the lsd??


I also noticed the "misfiring" but was told that everything was okay, maybe I wasn't used to this kind of V8

ms_

I wish i could find where the noise is coming from!! Although mine doesn't have the LSD option so not sure about that..

Hmm, best practice would be to jump in another and see if it does the same!

average joe

I had a miss-fire just at idle and just felt like a shudder through the car every now and then. No CEL and no codes, and no change in performance.

I changed the plugs out and that cured the fault.

Ingenieur

A V8 is not inherently balanced
There are resultant forces (and harmonics thereof) that are unchecked
Makes the engine feel like it's misfiring, not 'smooth', 'wobbles'

They can balance most of it out but must pick a freq range
They pick the torque and power peaks not idle

An inline 6 IS inherently balanced
No resultant uncancelled forces
Smooth as a turbine


Any combustion engine engineering text details this for all configurations
V12, v4, etc
Usually up to 3rd order harmonics
After that they are diminished to where they are not an issue