Auxiliary Air Valve

1. Install a suitable tachometer onto engine as per manufacturer's instructions.
2. Using fingers, pinch hose connecting air intake duct and auxiliary air valve and check engine speed.
3. With engine cold, engine idle speed should drop as hose is pinched. With engine at normal operating temperature, reduction in engine speed should be within 100 RPM when hose is pinched. On models equipped with cruise control, replace hose between tee connector and air intake duct with a long hose.
4. With engine started and auxiliary air valve at normal operating temperature, engine speed should drop gradually until specified engine idle speed is obtained. If engine speed will not drop, proceed as follows:
a. Using a suitable ohmmeter, check resistance of auxiliary air valve.
b. Disconnect electrical connector from auxiliary air valve and measure resistance between connector terminals.
c. If resistance value obtained is zero or infinity, replace auxiliary air valve.
5. Check source voltage as follows:
a. Disconnect electrical connector from auxiliary air valve and check voltage on harness side.
b. With engine operating, voltage reading obtained should be 12 volts or more.
c. If voltage reading obtained is lower than 12 volts or zero, check harness. Repair or replace as required.