Vacuum Delay Valve
NOTE:
If vacuum delay valve is stamped with an arrow, install with arrow facing intake manifold vacuum source.
- Disconnect the chamber-to-vacuum delay valve sensing tube at the chamber. Connect a vacuum gauge to the tube.
- Disconnect the air control valve-to-vacuum delay valve at the air control valve and connect it to the intake manifold. Start the engine and record the vacuum reading.
- Disconnect the tube from the intake manifold and measure the required time for the vacuum reading to decrease by 11.8 in. Hg from reading taken at idle. If time is not within specifications, replace the delay valve.