Anti-AFTERBURN Valve
- With engine idling at normal operating temperature, check manifold vacuum signal line to valve for presence of vacuum. If vacuum is not present, check vacuum line for kinks, pinches and proper routing.
- Remove vacuum line from valve for several seconds. Reconnect signal line. A change in RPM should be noted.
- Place hand over bottom of anti-afterburn valve (fingers apart). Increase engine speed to about 2500 RPM. Quickly release throttle. After throttle is released, air should be drawn in through bottom of valve for 1-2 seconds.
- If anti-afterburn valve does not respond as noted in steps 2) and 3), replace valve.
Courtesy of FORD MOTOR CO.