OUZO Power

Wife took the ML550 out the other night and brought it back with a check engine light. 2 codes read.

P0016 (intake camshaft sensor on right cylinder bank) and P0017 (exhaust camshaft sensor on right cylinder bank).

the check engine light went out on it's own.

But at deceleration or light steady throttle I hear a scrapping sound from the front. At heavy load or when I press on the brakes it's not present.

The engine serial number falls well past the range of those engines that were part of the class action lawsuit. So the Idler Gear is the updated one.

Anyone else had something similar happen to them? How bad do you think this is going to get?

OUZO Power

Also should add that if I rev the car in neutral there are no noises as described above when I let off the throttle. If it had to do with the idler gear wouldn't it be repetitive even in neutral?

OUZO Power

I've concluded it's not the engine. Even though it threw codes they went away. Took it for a spin.
1) Stopped and revving the engine produced no abnormal sounds.
2) Under acceleration no sounds.
3) Lift off the throttle and sounds start. Something rotating making a thump thump thump. Like a nail stuck in a tire but not a nail sound. A blunt sound.
4) Lift of throttle and switch to neutral and coast. Sound is still there.
5) Touch the brakes and the sound goes away. Lift off heavy braking no sound. Lift off lighter braking and sound returns but not as loud.
It has to either do with the brakes, CV joint or even the propeller shaft.
Ruling out front differential. I recently changed the fluids and they were clean. Same goes for the transition. Plus the sound would be more pronounced and under throttle if that was the case.

OUZO Power

So the thumping sound was the front wheel bearing. It's getting replaced now.


As for the CEL we are going to wait and see if it comes on again. Hoping we cleared this one and it was an isolated hicup.