Anybody know what the ignition timing advance should be on a 1994 E500?

It is not adjustable. At idle it should be somewhere in the 8-12 degree range.

Although this won't help for tune-ups, ignition timing is mildly adjustable via plug-in EZL resistors...used to compensate for fuel quality in different markets. Just FYI...

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Dean Albrecht
"Lead, follow, or better yet, get out of the way!"E500 owners motto

If you're lucky enough to get a Euro spec w/ trimming plugs you can adjust the EZL and LH Easily..
That said, better just to be Sure your ignition system is in Proper order. M119's Love to beat up their caps and rotors. Arc'd out wires are NG as well.

If you want a bit more power, get yourself a 92 LH module w/ WOT enrichment. Contact Dave via amgdave@gmail.com he's usually got a Good/tested unit on the shelf.

jonathan

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Blue Ridge Mercedes
Jonathan Hodgman
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Enthusiast Service, Restoration & Tuning.
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