2003 BMW E36 Engine And Engine Coolingexhaust System Problems

DOUBLE VANOS SYSTEM ON SEVERAL MODELS OF BMW FROM 1999 TO 2006, HAVE DEFECTIVE VANOS SYSTEMS. THE E39 DOUBLE VANOS (VARIABLE VALVE TIMING UNIT) HAS A MALFUNCTION PROBLEM. THIS DOUBLE VANOS CAN BE FOUND ON 6-CYL ENGINES M52TU, M54, AND M56, FOUND IN SEVERAL MODEL CARS, E39, E46, ETC, YEARS 99-03. THE MALFUNCTION SYMPTOMS ARE ALMOST ALL SUBTLE AND MOSTLY GO UNNOTICED. THEY INCLUDE LOWER GAS MILEAGE, LOWER PERFORMANCE, DEGRADED EMISSIONS CONTROL, AND POSSIBLY OTHERS. THE M52TU ENGINE (99-00) HAS ONE FURTHER MALFUNCTION SYMPTOM WHICH IS FAR FROM SUBTLE. IT OCCURS ON COLD WEATHER COLD ENGINE STARTS AND TAKES THE FORM OF REPEATED ENGINE ATTEMPTED STALLS AND POSSIBLY A COMPLETE ENGINE STALL. THE ENGINE RPMS DROP DRAMATICALLY AND THEN RECOVER. THIS THEN REPEATS AFTER A FEW SECONDS OF STEADY IDLE. THE PROBLEM CAN BE MORE DEFINITIVELY DIAGNOSED BY DISCONNECTING THE VANOS INTAKE OR EXHAUST SOLENOID ELECTRICAL CONNECTOR. *TR