ml3504matic____

Hi All,

At 190,000KM and am experiencing rattle on start up. I've bought the tensioners, and screws, but I've heard so many different answers as to how this can be remedied.

Option A:
Replace Tensioners only along with new Check Valves.

Option B:
Sprockets + Tensioners and Check Valve.

I've been told majority of the time it's just tensioners, but I've eheard so many conflicting things as to what it is.

https://youtube.com/video/tL82Dae8tbU/edit

CaliBenzDriver

​​​​​It won't hurt to start with conservative A only then progress with more comprehensive B.

At 200,000 km you're likely due for option B.

The question then is how many VVT gears :

• Passenger intake
• Both Intakes
• All four intakes + exhausts

Quint22

Dont have that engine but imho from reading how to do it replace as much as possible that ever requires it. Going in once vs going in couple of times is worth it if doing yourself. If paying may as well since most of cost is interference.

CaliBenzDriver

Quint I 100% subscribe to grouping maintenance procedures intelligently to save time, plus "do it once do it right!". In fact it would be interesting to have a thread on "item groupings".

B is both fairly extensive and expensive. The HPFP, fuel rail and injectors need to be removed to access the two valve covers.
Then the VVT gear are around $700Ea. and pairs are best to keep engine balanced.
Passenger side intake only is a shortcut for profit not for better results.

Avoiding B if possible with A only is fair. The VVT freeplay can be tested during tensioner replacement.

S-Prihadi

4 x VVT phasor/sprocket
4 x VVT oil control valve
all these 8 components ..................... are not cheap.

Get someone to scope the Bank 1 and Bank 2 intake VVT/phasor and the crankshaft.
next
Bank 1 and Bank 2 exhaust VVT/phasor and the crankshaft.
While engine being crank to start.

The bad one will be shown on how the pulse wheel signal is jumping around as the phasor hits left and right limit without maintaining proper stable position.
The sound is coming from here, see the video below :




200K KM is already good. Them VVT are consumeable items, its just a long life one but consumeable nevertheless, same as intake/exhaust valves and piston rings and liners