92 300CE Transmission Issue

[jstgermaine]

I think I figured out my stalling issue in a previous post...which of course means that something else must go wrong...

After I installed the new ignition parts today and started up the car, I decided to tap the throttle to see if I still had a slight miss from idle. The good news is, no miss...

The bad news...

...when I tapped the throttle I thought I felt the car actually MOVE! Naa...must have just been me being lightheaded from carb overload (McD's for lunch)...so I did it again...

...sure as *****....it did move!! The harder I stabbed the throttle, the more apparent the movement forward was...

...what would cause this?

[bwheitman]

I have noticed that there is the same issue with all MB's put it in nuetral, pop up the back wheels and with the engine running the wheels will spin, It is just the way I have always noticed them to be, Does it do this while in park?
Brian

[jstgermaine]

Hi Brian,

Never tried it in neutral...the forward movement was while the car was in park. It would actually move up to the point where the trans would catch (much like if you put the car in park on a hill, where it would roll forward or backward a touch until the trans caught).

[bwheitman]

Mine does that as well on the level surface in the garage, it will move against the lock while the engine is running, I always use my parking brake. I don't know if it is normal, but every MB I have had does this, and I know because every MB I have had will eventually develop some strange noise that requires diagnosis with the back wheels off the ground, one was a rear bearing, another was a driveshaft out of balance, etc, etc. I wouldn't worry about it, but it is strange.
Brian

[BenzRepair]

The movement is caused by a leaking manual valve in the valve body, or a leaking/sticking valve in the valve body (unless you are saying that the car is moving more than 6 inches, in which case likely your linkage is out of alignment or worse). Some cars will start doing this before VB failure due to excessive filter service intervals ("paper" filters that MB sells will blow out after so much filtering, allowing unfiltered fluids to travel through the valve body), but yours is likely just normal wear and is nothing to be concerned about.