LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Mercedes Benz >> 1987 >> 560SL >> Repair and Diagnosis >> Engine Performance >> System >> Fuel Evaporation System >> Testing >> System Check
April 5, 2026: LEMON Manuals is launched! Read the announcement.

System Check

  1. Disconnect hose between purge valve and canister at canister. Place finger over hose end. Slowly increase engine speed to 3000 RPM. No vacuum should be present at idle. Vacuum should gradually increase with engine speed.
  2. If no vacuum was present at hose, trace hose back to throttle valve housing. Blow through connection on housing. Ensure hose is clear.
  3. If vacuum is still not present, remove White/Purple/Black hose from purge valve. If vacuum is now present, replace purge valve. If vacuum is not present, replace thermo valve.
scientia non olet · About LEMON Manuals