Control Valve Vacuum Diaphragm Check
- With engine warm and idling, disconnect neutral switch.
- Disconnect vacuum hose from air control valve vacuum diaphragm. Increase engine speed to 1160 RPM. Verify that vacuum signal exists below 1160 RPM. Above 1160 RPM, vacuum signal should bleed off when air control solenoid is de-energized by ECA.
- Using hand-held vacuum pump, apply vacuum to air control valve diaphragm. See Fig 1
. Valve should open at about 5.5 in. Hg. If valve fails to open, replace vacuum diaphragm.
Courtesy of FORD MOTOR CO.