0015407097
Mercedes (OE)
Vacuum Valve; 3-Way Switchover Valve with 3 Vacuum and 2 Electrical Connections
Multiple use relay for EGR, fast idle, transmission control, shift-point, starting booster, manifold pressure compensator, air pump, etc.

1992 500SL

How do you test this valves? there are 4 valves under the left hand cover next to the engine.

Trying to find the vac problem that causes the erratic rough idle,for example today coming back from lunch, at the stop light with air cond OFF the car was idling fine, I wasn't driving very constant without pushing it prior to that stop, 2 minutes later, after arriving home when I set it on Park the rough idle came back.

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Thanks, Juan