Celicasaur

I know that on some engines (K20, 2ZZ) from other manufacturers, when removing a VVT cam gear, compressed air must be blown into one of the oil ports in order to help 'unlock' the internals (you twist the camgear anti-clockwise once the compressed air is fed into it and you should hear a nice click).

Upon resinstallation, the camgear gets twisted back and clicks into place, before you torque it down to the camshaft. If this isn't done, the camgear won't be able to work it's magic and adjust the camshaft as it needs to.

Does the M156 require a similar process? I'm wondering if the shop that did the install might have missed a trick here....either that, or it's a different process for this engine.

Wondering if camgears are my issue for the lack of peak power. Is there any way to check/find out if they are in fact the problem?

Plutoe

You are dangerous, hopefully the car in question is yours not a customers----in any event put the car on a dyno and all will be clear!!

Celicasaur

I'm so confused as to what you meant....but not to worry.

Anybody with first hand experience or knowledge of how these cam adjusters are meant to be removed and then reinstalled?

mr747

if there not set correct you will get CEL codes 100% i have seen this happen previously

They should be marked prior to taking them out to make sure they go back in

MERC63 should be able to shed some light on this matter

Celicasaur

Ahhh ok, fair enough. Thanks Brad. I guess the only thing I can do to check is either have the car scanned for correct operation when it goes to MB for it's annual service (19th May) or I could remove the valve cover and manually rotate the crank pulley to see if there's any slack in the cam gear.

I refuse to fit the headers and throttle bodies until I've solved this mystery.

Merc63

There isnt slack in the cam gear, the gear is two pieces, one piece is spring loaded to keep constant pressure on the ring gear.

If you have the MB cam tools, you can loosen off the big bolt holding the phaser to the cam, put the tools on and set the phaser to the proper location. You'll need the WIZ documents for this... The engine has to be at 40degrees with the plate on top of the cam and the flat bar at the back of the cam. Then you install the front cam plate to set the phaser position. If they are installed incorrectly, you should get a check engine light right away.

I think if you remove the phaser without locking the two gears and they move, I don't know what happens then...

Celicasaur

Hmm...so going by what you're saying, it must be fitted correctly on my car I guess.

I've read in older threads where members have reported much improved performance from replacing their cam gears at higher mileage. Mine is about to hit 80k miles, so I wonder if that's something that applies here. I guess there's only one way to find out and there it's not cheap.

I find it hard to believe that the Eurocharged tune on my car can be so bad that it has managed to kill the top end of the power. My friend has Kleemann cams and a eurocharged tune on his C63 and the damn thing rips through gears, esp at high rpm.

Hmm...I wonder if the MB tech's will be able to do some live data logging to test the cam gears for optimal efficiency.