Improper Door Action
- If door did not open, check for door binding. If okay, disconnect hose at "T" fitting leading to air bleed valve. Plug fitting. Crank engine for about 5 seconds. Air control valve door should rise and remain up for at least 3 seconds. If door rises and stays up for at least 3 seconds, replace air bleed valve and repeat test.
- If door does not rise, disconnect vacuum hose from air control diaphragm. Connect hand-held vacuum pump to diaphragm fitting. Apply vacuum. Air control door should rise and remain in up position. If door does not rise or stay up, replace air control diaphragm. If door rises and stays up, replace check valve and retest.