Acura Coupes and Sedans 1986-1993 Repair Guide

Charcoal Canister



  1. Start the engine and allow it to warm to normal operating temperature or until the cooling fan comes on. Hold the engine at 2000 rpm and check for vacuum at the vacuum hose.
  3. If there is no vacuum, proceed with Step a. If there is vacuum, skip ahead to Step 3.
    1. Disconnect the electrical connector and check again for the presence of vacuum. If vacuum is still not present, inspect the vacuum hose routing. If the hose routing checks out OK, replace the purge control or cut-off solenoid valve.
    3. If there is vacuum present after disconnecting the electrical connector, inspect the wiring for an opening or short. If the wire checks out OK, replace the ECU with a known-good one and recheck.

  5. If vacuum is present after starting the vehicle and allowing the engine to warm up, connect the hose and remove the fuel filler cap.
  7. Remove the canister purge air hose and connect the hose to a vacuum gauge. Start the engine and raise the engine speed to 3500 rpm. Vacuum should appear on the gauge within 1 minute. If there is vacuum, the evaporative emission control system is OK.
  9. If there is no vacuum present, connect a vacuum gauge to the canister purge hose and raise the engine speed to 3500 rpm. If there is vacuum present, replace the canister and retest. If there is no vacuum present, inspect the purge hose and throttle body port for blockage.