EXCESSIVE SPARK KNOCK ON 1982 FIRENZA MODELS EQUIPPED WITH CRUISE CONTROL AND NO A/C CAN BE CAUSED BY A MIS-ROUTED VACUUM SENSOR HOSE. FIG. 13 SHOWS THE INCORRECT ROUTING: IE THE VACUUM SENSOR HOSE CONNECTED TO A VACUUM TEE IN THE MAIN VACUUM HARNESS. REROUTE THE VACUUM SENSOR HOSE BY DISCONNECTING THE HOSE FROM THE VACUUM TEE AND CONNECTING IT TO THE LOWER PORT OF THE 4 PORT CONNECTOR ON THE INTAKE MANIFOLD. CAP OR DISCARD THE VACUUM TEE.
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