Cold Engine
- Disconnect the air suction lower hose at the anti-afterburn valve. Start the engine and quickly raise the engine speed to 3500 RPM and close the throttle suddenly. If there is no vacuum, go to step 4).
- If there is vacuum, check for voltage at anti-afterburn control solenoid valve (Blue/Yellow wire). If there is no voltage, got to Trouble Shooting. If there is voltage, disconnect lower vacuum hose from anti-afterburn valve. Check for vacuum at the hose.
- If there is no vacuum, check for leaks or disconnected hose. If there are no defects, replace the anti-afterburn control solenoid valve and retest. If there is vacuum, replace the anti-afterburn valve and retest.
- Jack up the front of the vehicle and support with safety stands. Block the rear wheels and set the parking brake. Place the shift or selector lever in second or 2 position and accelerate. Suddenly release the throttle and check for vacuum during deceleration above 15 MPH.
- If there is vacuum, go to Hot Engine test. If there is no vacuum, check for voltage at the anti-afterburn control solenoid valve above 15 MPH. If there is voltage, go to Trouble Shooting. If there is no voltage, disconnect the lower vacuum hose from the anti-afterburn valve and check for vacuum above 15 MPH.
- If there is vacuum, replace the anti-afterburn control valve and retest. If there is no vacuum, disconnect the upper vacuum hose from anti-afterburn valve and check for vacuum. If there is no vacuum, check for disconnected hoses or leaks and retest. If there is vacuum, replace the anti-afterburn valve and retest.
NOTE:
For California models only, see PULSE AIR SYSTEM tests before proceeding to Hot Engine tests.