Feedback Control System Inspection

Fig. 40 Component Location For Frequency Solenoid Valves A and B:

1. With the engine at normal operating temperature, disconnect the #14 hose from the power valve (on the back side of the carburetor) and install a plug in the hose.
2. Start the engine and check that frequency solenoid valves A and B are operating (making a continuous 'clicking' noise) when the engine speed is raised to approx. 2500 rpm. (It may be easier to determine if the valves are working by placing your hand on each valve and feel them).
a. If either of the valves fail to operate, replace it and re-test.
b. If both valves fail to operate, check frequency solenoid valve A.

3. Connect the #14 hose back to the power valve. With the A/C OFF (if equipped) check that frequency solenoid valves A and B do not operate with the engine at idle.