I have a '85 190e 2.3. How do I go about finding a vacuum leak? When the car is idleing in park, the economy gauge shows a leak (about 1/8 of the guage). When I put the car in rev. drive or anything else, the leak gets worse (up to half guage then back don to 1/4). Also when I put the car in drive the engine looses a lot of idle speed. The car will also shudded, like it is missing up until about 1100 RPM's, then it runs smooth. Has no power until it gets over that 1100 rpm. Is this a vacuum leak, or should I sell it quick?!?!?