LOOSE EGR SOLENOID CONNECTION ENGINE SURGE/TOO MUCH EGR

A SURGING CONDITION ON A 3.0L ENGINE COULD BE CAUSED BY A LOOSE PULSE WIDTH MODULATED (P.W.M.) EGR VALVE ELECTRICAL CONNECTOR. THE P.M.W. SOLENOID PACK IS MOUNTED ON THE ROCKER ARM COVER NEXT TO THE COWL PANEL. (SEE FIGURE 1) IF THE CONNECTOR IS LOOSE, THE ELECTRICAL CONNECTION IS REMOVED FROM THE SOLENOID, WHICH ALLOWS FULL MANIFOLD VACUUM TO THE EGR VALVE (SEE FIGURE 2 AND 3). WHEN CHECKING AND INSTALLING CONNECTOR, SQUEEZE LOCKING TAB TO ASSURE A POSITIVE LOCK WITHIN THE P.W.M. HOUSING. ALSO CHECK THE VACUUM HARNESS ON THE P.W.M. SOLENOID PACK TO ASSURE THE PORTS ON THE PACK ARE INSTALLED INTO THE HARNESS CORRECTLY. A VACUUM LEAK CAN CAUSE A ROUGH IDLE AND IS USUALLY DETECTED BY A 10 DEGREE OR BELOW DWELL READING (SEE FIGURE 4). OTHER POSSIBLE ITEMS THAT COULD CAUSE POOR DRIVEABILITY; * LIGHT SURGE MAY BE CAUSED FROM TIMING SET BELOW SPECS. * VACUUM LEAKS AT: A. EFE ASSEMBLY TO VACUUM PIPE B. HOSE AT CARB. LOCATION 'V' CUT C. HOSE OFF OR NIPPLE CRACKED AT AIR MANAGEMENT VALVE D. INTAKE MANIFOLD E. A/C VACUUM TANK F. EFE/EGR SOLENOID HOSES REVERSED G. AIR CLEANER VACUUM HOSE (THERMAC) H. A/C WATER VALVE HOSE DISCONNECTED I. EFE CHECK VALVE CRACKED OR BROKEN

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