Please explain how variable valve timing on my M104 works...
 

I own a 1996 E320 equiped with a M104 engine. Please explain how the variable valve timing operates and what the symptoms are when it doesn't function correctly. At times, my E320 feels a little sluggish off the line and I'm wondering if valve timing might be the culprit.

Chris

Intake valve timing advances 20 degrees @ 3K rpm/no load.

You can test for voltage at advance solinoid....

On-Off or Continous?
 

Is the VVT of the M104 is ON-Off or Continous?

If it's ON-Off...at what RPM is it ON and what RPM is it Off?

Thanks in advance.

NPK

The 3k mark is the on, when crossing 3k and accelerating. It's also the off, when crossing 3k and decelerating.

I don't understand your question about on/off vs continuous. The intake valve timing advances 20degrees at 3000 rpm and stays advanced until redline. At any rpm below 3000, the intake valve timing is non-advanced.

The 3K RPM spec is w/o load only!

When driving, under load the cam advance happens at 1500 rpm & goes back to retard at 4200 rpm.

As suggested it is only ON/OFF system.

SO Yes, the lack of cam advancement could cause a hesitation.

The cam advance @ 1500 statement confuses me - I feel a sudden surge of power at about 3250 RPM on my E320. I figured that was when the timing was advancing???

On-Off is like 20deg when On and 0deg when Off.(so it's either 20deg or 0 deg only and nothing in between)

Continous is like 0deg when off and slowly increases, then 2deg, then 5 deg, then 10 deg till 20Deg

Thanks

At 3200 you are feeling the variable intake flap change positions.

Changing the intake runner length is worth 20+ HP's.

Cool. Makes sense now...