1999 Buick LesabreLIMITED

VEHICLE DESCRIPTION: PASSENGER VEHICLES EQUIPPED WITH 4T65E AUTOMATIC TRANSMISSIONS. THESE VEHICLES FAIL TO CONFORM TO THE REQUIREMENTS OF FMVSS NO. 102, "TRANSMISSION SHIFT LEVER SEQUENCE." A RETAINING CLIP, WHICH SECURES THE MANUAL VALVE TO THE LINKAGE OF THE TRANSMISSION DETENT LEVER, CAN BECOME LOOSE UNDER A COMBINATION OF POSSIBLE DRIVER SHIFTING MANEUVERS AND ALLOW THE LINK TO BECOME DISCONNECTED FROM THE MANUAL VALVE.

ON CERTAIN PASSENGER VEHICLES EQUIPPED WITH 3800 V6 (L36) ENGINES AND CERTAIN DELPHI FUEL PRESSURE REGULATORS, THE REGULATORS HAVE A MUCH HIGHER THAN USUAL RATE OF FUEL LEAKS. A LEAK CAN ALLOW FUEL TO ENTER THE INTAKE MANIFOLD THROUGH A VACUUM LINE. IF THE ENGINE DOES NOT START WHEN CRANKED, THE FUEL FROM THE LEAKING REGULATOR AND A MISTIMED SPARK CAN CAUSE A BACKFIRE.