1998 Mercury Mountaineer speed control problems

Defect

VEHICLE DESCRIPTION: SPORT UTILITY VEHICLES EQUIPPED WITH 4.0L SOHC ENGINES AND STILL RETAIN THE ORIGINAL THROTTLE BODY (PART NUMBERS 97JF-9E926AB OR 97JF-9E926-AC). SOME OF THE ORIGINAL THROTTLE BODIES INSTALLED ALLOWED A GAP BETWEEN THE PLATE AND BORE TO BE BUILT TOO NARROW. THIS REDUCED CLEARANCE ALLOWED THE ENGINE DEPOSITS NORMALLY PRESENT IN THE THROTTLE BODY TO CONTACT OR BRIDGE THE GAP. IF THE ENGINE DEPOSITS BRIDGED THE GAP BETWEEN THE THROTTLE PLATE AND BORE AND THEN HARDENED, ON THE INITIAL APPLICATION OF THE ACCELERATOR PEDAL AFTER THE ENGINE HAS COOLED, THE OPERATOR WOULD NEED TO APPLY ADDITIONAL FORCE TO THE ACCELERATOR PEDAL TO BREAK THE BRIDGE.

Consequence

THIS COULD RESULT IN ENGINE SURGE WHEN THE ACCELERATOR PEDAL BREAKS FREE.

Remedy

DEALERS WILL REPLACE THE ORIGINAL THROTTLE BODIES.

Defect

VEHICLE DESCRIPTION: CERTAIN 1997-1999 RHD EXPLORER EQUIPPED WITH 4.0L OHV/SOHC ENGINES AND CRUISE CONTROL BUILT FROM MAY 29, 1996 THROUGH MARCH 4, 1999; 1998-1999 EXPLORER/MOUNTAINEERS EQUIPPED WITH 4.0L OHV/SOHC OR 5.0L ENGINES OR 1998-1999 RANGERS EQUIPPED WITH 2.5L, 3.0L FFV/EFI OR 4.0L ENGINES AND CRUISE CONTROL BUILT FROM JANUARY 5, 1998 THROUGH MARCH 4, 1999; 1998-1999 MUSTANGS EQUIPPED WITH 3.8L, 4.6L 2-VALVE OR 4-VALVE ENGINES AND CRUISE CONTROL BUILT FROM MARCH 2, 1998 THROUGH MARCH 4, 1999; 1999 F250/F350/F450/F550 (OVER 8,500 LBS.) TRUCKS EQUIPPED WITH 5.4L OR 6.8L ENGINES AND CRUISE CONTROL BUILT FROM MARCH 2, 1998 THROUGH MARCH 4, 1999; AND 1999 F-53 STRIPPED CHASSIS EQUIPPED WITH 5.4L OR 6.8L ENGINES AND CRUISE CONTROL BUILT FROM MARCH 2, 1998 THROUGH MARCH 4, 1999. A CRUISE CONTROL CABLE CAN INTERFERE WITH THE SPEED CONTROL SERVO PULLEY AND NOT ALLOW THE THROTTLE TO RETURN TO IDLE WHEN DISENGAGING THE CRUISE CONTROL.

Consequence

IF THE CRUISE CONTROL IS USED AND THIS CONDITION IS PRESENT, A STUCK THROTTLE COULD RESULT, WHICH COULD POTENTIALLY RESULT IN A CRASH.

Remedy

DEALERS WILL REPLACE THE CRUISE CONTROL CABLES. AT THE PRESENT TIME, THE REPLACEMENT CABLES ARE NOT AVAILABLE. CUSTOMERS ARE BEING ADVISED NOT TO USE THE CRUISE CONTROL SYSTEM UNTIL A REPLACEMENT CAN BE MADE.