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P1540 Diagnostic Trouble Code Discussion for January 2009

Air Conditioning Refrigerant Over-Pressure - Air Conditioning Disabled

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Trouble Ticket Help Requests for DTC P1540
Help Request Posted
1999 Mazda Millenia S 2.3L Poor Idle Quality, Hesitation, Cuts out, Misfire, MIL Lamp on, CNT REV OVER 2200RPM VIN: JM1TA2227X
P1540: Air Bypass Valve System. Car starts fine, idle is poor, and clearly misfiring. After 2-3 minutes of driving "TCS off" and TCS Lamp comes on and engine can not rev over 2200 rmp. Had prior O2 sensor codes fixed by replacing downsteam sensors one was cracked. Had replaced spar...
January 24, 2009