Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
1985 Mercedes Benz 190D AutomaticFACTORY OEM SERVICE PROCEDURE
Vacuum Control Valve
- Connect Vacuum Tester (116 589 25 21 00) to vacuum control valve and check vacuum at idle (9.6-11 in. vacuum). With engine stopped and throttle linkage at full throttle stop, vacuum should be 0 in. vacuum. If test is okay, end of test. If test is not okay, go to step 2). See Fig 1 .
- Test vacuum lines and check vacuum pump. Adjust vacuum control valve and replace, if necessary.
Factory Service Tools
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.