Vac leaks create lean running conditions.

At 200K plus, you should have resealed the intake manifold assembly at least once. I did mine about four years ago around 155k, 560 drove totally different after the procedure.

Not sure when M116/7s need valve guides, I have heard 250-300k area. This is a spendy job as you need to install helicoils in the block, on top of the valve work, labor (yours or shops?), and be foolish not to pull timing cover for lower guides.

__________________
I'm not a doctor, but I'll have a look.

'85 300SD 245k
'87 300SDL 251k
'90 300SEL 326k

Six others from BMW, GM, and Ford.

Liberty will not descend to a people; a people must raise themselves to liberty.[/IMG]