Hi, new member and need some help. I boutht a nice 1986 420SEL and my wife has been driving it for a year. It recently has started to idle rough and economy guage indicates a vacuum leak. I took it to a local mechanic an he smoked tested the systems and said it needed gaskets a hoses from the intake manifold, injectors,fuel distributor, including vacuum hoses, for a price of $600. I would like to do the work myself but would feel more comfortable with a repair procedure for this operation. Does anyone know where I could get a procedure to do this? thanks John

Thomas Pindelski, a contributor to this forum, has a detailed write-up on intake manifold overhaul on his subscription-only website, pindelski.com. I would not have been able to undertake this task on my 500 SEC without his site, though as it turned out I went even further than he did in the pictorial. (Perhaps the most glaring omission is a discussion of the correct mounting of the throttle position switch. You do not want to get this wrong given the difficulty in getting back at it later.) His subscription fee is ridiculously modest and will pay for itself many times over just on this one job.