Auxiliary Air Valve (Idle Speed): Testing and Inspection

Fig. 74 Testing Auxiliary Air Valve:

1. Disconnect air cleaner hose from throttle body.
2. Start engine. Ensure that there is air continuity at the auxiliary air valve port under the following conditions:
a. When coolant temperature is below 104°F, block auxiliary air valve port, Fig. 74. Ensure engine speed drops.
b. When coolant temperature is above 146°F for 3 cylinder engines and 158°F for 4 cylinder engines, block auxiliary air valve port and ensure engine speed does not change.
3. If auxiliary valve exhibits malfunction, replace throttle body.