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2003 Lincoln Navigator

Owner reports · Recalls · Investigations

More warning signs than most Navigator years

Owner complaints for the 2003 Lincoln Navigator are substantially higher than the model-year median of 30.

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When problems were reported

Mileage at the reported incident

91 reports with mileage · 36 unknown

NHTSA’s mileage field refers to the reported incident, not necessarily the filing date. This shows report counts, not the likelihood of a failure.

What to inspect

Issues worth paying extra attention to based on owner reports.

  • Suspension. Review the 38 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Electrical System. Review the 22 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Structure. Review the 18 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →

NHTSA owner reports · September 18, 2026 snapshot.

6 crash reports3 fire reports11 injury reports

Engine complaints

4 reports
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75,000 miles · Aug 26, 2024
Engine

The contact owns a 2003 Lincoln Navigator. The contact stated while driving 35 MPH, there was an abnormal sound coming from the engine compartment, prompting the contact to pull over to the shoulder of the roadway. The vehicle was towed to the residence. No warning lights were illuminated. The vehicle was towed to the dealer, wh…

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The contact owns a 2003 Lincoln Navigator. The contact stated while driving 35 MPH, there was an abnormal sound coming from the engine compartment, prompting the contact to pull over to the shoulder of the roadway. The vehicle was towed to the residence. No warning lights were illuminated. The vehicle was towed to the dealer, who diagnosed a failure with the rocker arms, and that the engine lacked adequate compression in cylinders #2 and #3, resulting in engine damage. The contact was informed that the engine needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure but provided no assistance. The failure mileage was 75,000.

NHTSA ODI #11610921

107,000 miles · Jun 16, 2016
Engine

COMING HOME FROM A TRIP ENGINE STARTED TO MISFIRE. COME TO FIND OUT THE # 3 SPARK PLUS EXPLODED DESTROYING THE COIL AND AND THREADS HOLDING THE SPARK PLUG IN. CAUSING THE NEED TO RE TAP THE THREADS.

NHTSA ODI #10874720

79,000 miles · Aug 29, 2015
Engine

JUST DRIVING IN A 45 MPH, WHEN HEARD LOUD BANGING COMING FROM ENGINE. PULLED OVER AND HAD CAR TOWED IN FOR REPAIR. ENGINE BLEW OUT A SPARK PLUG.

NHTSA ODI #10760148

159,000 miles · Dec 29, 2014
Engine

WE WERE DRIVING DOWN THE HIGHWAY AT APPROXIMATELY 70MPH, WHEN I HEARD A LOUD POP AND CLANKING NOISE ON THE DRIVER'S SIDE FRONT ENGINE AREA. I WAS DRIVING WITH MY WHOLE FAMILY IN THE SUV. WE WERE ABLE TO STILL DRIVE IT TO A MECHANIC. THE MECHANIC DIAGNOSED IT AS A "BLOWN-OUT SPARK PLUG". HE SAID THE SPARK PLUG HAD COME OUT OF THE…

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WE WERE DRIVING DOWN THE HIGHWAY AT APPROXIMATELY 70MPH, WHEN I HEARD A LOUD POP AND CLANKING NOISE ON THE DRIVER'S SIDE FRONT ENGINE AREA. I WAS DRIVING WITH MY WHOLE FAMILY IN THE SUV. WE WERE ABLE TO STILL DRIVE IT TO A MECHANIC. THE MECHANIC DIAGNOSED IT AS A "BLOWN-OUT SPARK PLUG". HE SAID THE SPARK PLUG HAD COME OUT OF THE ENGINE BLOCK. HE SAID IT IS A COMMON PROBLEM ON THAT ENGINE AND THERE WAS A SPARK PLUG KIT FOR IT. HE USED THE KIT, AND IT ONLY HELD FOR ABOUT 2 MONTHS. IT NOW HAS LOST POWER, SHAKES, AND POOR GAS MILEAGE. THE REPAIR KIT OBVIOUSLY IS NOT AMPLE FOR THIS PROBLEM. *TR

NHTSA ODI #10668927

Official recalls

0

No recalls in this snapshot.

Model-level recall history does not show whether a particular VIN is affected or has received a repair. Check a VIN with NHTSA ↗

NHTSA investigations

1

DP05005 · Spark Plug Ejection From Cylinder Head

Opened Sep 22, 2005 · Closed Jan 4, 2006

Status: closed (inferred from source dates) · Engine And Engine Cooling; Engine And Engine Cooling:engine; Engine And Engine Cooling:engine:gasoline

ON SEPTEMBER 6, 2005, ODI RECEIVED A PETITION REQUESTING THAT THE AGENCY INVESTIGATE ALLEGATIONS OF ENGINE SPARK PLUG EJECTION IN CERTAIN MODEL YEAR 1997 THROUGH 2004 FORD VEHICLES WITH TRITON V-8 AND V-10 ENGINES.ODI RECEIVED A TOTAL OF 474 NON-DUPLICATIVE COMPLAINTS ON THE SUBJECT VEHICLES WHERE THE COMPLAINANT, OR THE DEALER REPAIRING THE VEHICLE, REPORTED THAT A SPARK PLUG DETACHED FROM THE CYLINDER AND/OR EJECTED FROM THE ENGINE.AS OF DECEMBER 8, 2005, ODI IS NOT AWARE OF ANY ALLEGATIONS WHERE THE ALLEGED DEFECT RESULTED IN A LOSS OF VEHICLE CONTROL, A CRASH, AN INJURY, OR A FATALITY IN ANY OF THE 10,319,810 SUBJECT VEHICLES.IN ADDITION, ODI IS AWARE OF ONLY TWO INCIDENTS WHERE THE VEHICLE STALLED WITHOUT RESTART.INFORMATION CONTAINED IN THE ODI CONSUMER COMPLAINTS AND OBTAINED FROM 72 TELEPHONE INTERVIEWS WITH COMPLAINANTS SHOWED THE FOLLOWING:(1) 99% OF THE COMPLAINTS WERE ON MY 1997 TO 2002 SUBJECT VEHICLES.(2) MOST THE COMPLAINANTS REPORTED HEARING A LOUD POP WHILE DRIVING OR UPON STARTING UP THE VEHICLE FOLLOWED BY A LOUD, REPETITIVE CLICKING OR POPPING SOUND.(3) MANY OF THE COMPLAINANTS REPORTED THAT THE POPPING SOUND WAS ACCOMPANIED BY SOME LOSS OF VEHICLE POWER; HOWEVER, IN 99% OF THE INCIDENTS REPORTED, THE VEHICLE DID NOT STALL.IN THE VERY FEW INCIDENTS WHERE THE VEHICLE DID STALL, MOST VEHICLES COULD BE RESTARTED.(4) ONLY A SMALL PERCENTAGE OF THE COMPLAINANTS CITED THAT THEY SMELLED GAS OR A SLIGHT BURNING SMELL WHEN THE INCIDENT OCCURRED.(5) IN ALL BUT A VERY FEW INCIDENTS, VEHICLE DAMAGE WAS LIMITED TO THE ENGINE.IN ONE INCIDENT, THE COMPLAINT REPORTED THAT THE FUEL RAIL WAS DAMAGED AND REPLACED AFTER ONE OF THE SPARK PLUGS EJECTED FROM THE ENGINE; HOWEVER, THE COMPLAINANT REPORTED THAT THE DAMAGE DID NOT RESULT IN ANY TYPE OF FUEL LEAK OR FIRE.IN ANOTHER INCIDENT, THE ONLY INCIDENT WHERE A FIRE WAS ALLEGED, THE COMPLAINANT REPORTED THAT NO FLUID LEAK WAS OBSERVED, BUT THAT A FIRE RESULTED AFTER THE SPARK PLUG HAD EJECTED FROM THE ENGINE AND HE HAD RESTARTED THE VEHICLE AND DRIVEN TO ANOTHER LOCATION.NONE OF THE COMPLAINANTS REPORTED ANY DAMAGE TO THE VEHICLE HOOD.(6) ONLY TWO COMPLAINANTS REPORTED THAT THEY OBSERVED WHAT APPEARED TO BE SOME DROPS OF FUEL COMING FROM THE CYLINDER WHERE THE SPARK PLUG HAD FAILED OR ON THE SPARK PLUG ITSELF; HOWEVER, EACH OF THESE COMPLAINANTS REPORTED THAT THERE WAS NO SMOKE OR FLAMES AS A RESULT OF HIS INCIDENT.AS THE PETITIONER NOTED, AND ODI?S ANALYSIS SHOWED, IT IS POSSIBLE FOR A SPARK PLUG TO DETACH FROM THE ENGINE CYLINDER THREADS IN THE SUBJECT VEHICLES.HOWEVER, ODI?S ANALYSIS OF 474 COMPLAINTS DESCRIBING SUCH INCIDENTS FOUND ONLY A VERY FEW ALLEGED ANY SAFETY-RELATED CONSEQUENCES.NONE OF THESE SHOWED ANY EVIDENCE OF A SERIOUS SAFETY CONSEQUENCE.GIVEN THE LARGE POPULATION AND RELATIVELY LONG EXPOSURE TIME OF THE SUBJECT VEHICLES, THE COMPLAINT ANALYSIS INDICATES THAT THE RISK TO MOTOR VEHICLE SAFETY FROM THE ALLEGED DEFECT IS VERY LOW.IN VIEW OF THE FOREGOING, IT IS UNLIKELY THAT NHTSA WOULD ISSUE AN ORDER FOR THE NOTIFICATION AND REMEDY OF THE ALLEGED DEFECT AT THE CONCLUSION OF THE INVESTIGATION REQUESTED IN THE PETITION.THEREFORE, IN VIEW OF THE NEED TO ALLOCATE AND PRIORITIZE NHTSA?S LIMITED RESOURCES TO BEST ACCOMPLISH THE AGENCY?S SAFETY MISSION, THE PETITION IS DENIED.

Additional source detail variants (3)

Engine And Engine Cooling:engine

ON SEPTEMBER 6, 2005, ODI RECEIVED A PETITION REQUESTING THAT THE AGENCY INVESTIGATE ALLEGATIONS OF ENGINE SPARK PLUG EJECTION IN CERTAIN MODEL YEAR 1997 THROUGH 2004 FORD VEHICLES WITH TRITON V-8 AND V-10 ENGINES.ODI RECEIVED A TOTAL OF 474 NON-DUPLICATIVE COMPLAINTS ON THE SUBJECT VEHICLES WHERE THE COMPLAINANT, OR THE DEALER REPAIRING THE VEHICLE, REPORTED THAT A SPARK PLUG DETACHED FROM THE CYLINDER AND/OR EJECTED FROM THE ENGINE.AS OF DECEMBER 8, 2005, ODI IS NOT AWARE OF ANY ALLEGATIONS WHERE THE ALLEGED DEFECT RESULTED IN A LOSS OF VEHICLE CONTROL, A CRASH, AN INJURY, OR A FATALITY IN ANY OF THE 10,319,810 SUBJECT VEHICLES.IN ADDITION, ODI IS AWARE OF ONLY TWO INCIDENTS WHERE THE VEHICLE STALLED WITHOUT RESTART.INFORMATION CONTAINED IN THE ODI CONSUMER COMPLAINTS AND OBTAINED FROM 72 TELEPHONE INTERVIEWS WITH COMPLAINANTS SHOWED THE FOLLOWING:(1) 99% OF THE COMPLAINTS WERE ON MY 1997 TO 2002 SUBJECT VEHICLES.(2) MOST THE COMPLAINANTS REPORTED HEARING A LOUD POP WHILE DRIVING OR UPON STARTING UP THE VEHICLE FOLLOWED BY A LOUD, REPETITIVE CLICKING OR POPPING SOUND.(3) MANY OF THE COMPLAINANTS REPORTED THAT THE POPPING SOUND WAS ACCOMPANIED BY SOME LOSS OF VEHICLE POWER; HOWEVER, IN 99% OF THE INCIDENTS REPORTED, THE VEHICLE DID NOT STALL.IN THE VERY FEW INCIDENTS WHERE THE VEHICLE DID STALL, MOST VEHICLES COULD BE RESTARTED.(4) ONLY A SMALL PERCENTAGE OF THE COMPLAINANTS CITED THAT THEY SMELLED GAS OR A SLIGHT BURNING SMELL WHEN THE INCIDENT OCCURRED.(5) IN ALL BUT A VERY FEW INCIDENTS, VEHICLE DAMAGE WAS LIMITED TO THE ENGINE.IN ONE INCIDENT, THE COMPLAINT REPORTED THAT THE FUEL RAIL WAS DAMAGED AND REPLACED AFTER ONE OF THE SPARK PLUGS EJECTED FROM THE ENGINE; HOWEVER, THE COMPLAINANT REPORTED THAT THE DAMAGE DID NOT RESULT IN ANY TYPE OF FUEL LEAK OR FIRE.IN ANOTHER INCIDENT, THE ONLY INCIDENT WHERE A FIRE WAS ALLEGED, THE COMPLAINANT REPORTED THAT NO FLUID LEAK WAS OBSERVED, BUT THAT A FIRE RESULTED AFTER THE SPARK PLUG HAD EJECTED FROM THE ENGINE AND HE HAD RESTARTED THE VEHICLE AND DRIVEN TO ANOTHER LOCATION.NONE OF THE COMPLAINANTS REPORTED ANY DAMAGE TO THE VEHICLE HOOD.(6) ONLY TWO COMPLAINANTS REPORTED THAT THEY OBSERVED WHAT APPEARED TO BE SOME DROPS OF FUEL COMING FROM THE CYLINDER WHERE THE SPARK PLUG HAD FAILED OR ON THE SPARK PLUG ITSELF; HOWEVER, EACH OF THESE COMPLAINANTS REPORTED THAT THERE WAS NO SMOKE OR FLAMES AS A RESULT OF HIS INCIDENT.AS THE PETITIONER NOTED, AND ODI?S ANALYSIS SHOWED, IT IS POSSIBLE FOR A SPARK PLUG TO DETACH FROM THE ENGINE CYLINDER THREADS IN THE SUBJECT VEHICLES.HOWEVER, ODI?S ANALYSIS OF 474 COMPLAINTS DESCRIBING SUCH INCIDENTS FOUND ONLY A VERY FEW ALLEGED ANY SAFETY-RELATED CONSEQUENCES.NONE OF THESE SHOWED ANY EVIDENCE OF A SERIOUS SAFETY CONSEQUENCE.GIVEN THE LARGE POPULATION AND RELATIVELY LONG EXPOSURE TIME OF THE SUBJECT VEHICLES, THE COMPLAINT ANALYSIS INDICATES THAT THE RISK TO MOTOR VEHICLE SAFETY FROM THE ALLEGED DEFECT IS VERY LOW.IN VIEW OF THE FOREGOING, IT IS UNLIKELY THAT NHTSA WOULD ISSUE AN ORDER FOR THE NOTIFICATION AND REMEDY OF THE ALLEGED DEFECT AT THE CONCLUSION OF THE INVESTIGATION REQUESTED IN THE PETITION.THEREFORE, IN VIEW OF THE NEED TO ALLOCATE AND PRIORITIZE NHTSA?S LIMITED RESOURCES TO BEST ACCOMPLISH THE AGENCY?S SAFETY MISSION, THE PETITION IS DENIED.

Engine And Engine Cooling:engine:gasoline

ON SEPTEMBER 6, 2005, ODI RECEIVED A PETITION REQUESTING THAT THE AGENCY INVESTIGATE ALLEGATIONS OF ENGINE SPARK PLUG EJECTION IN CERTAIN MODEL YEAR 1997 THROUGH 2004 FORD VEHICLES WITH TRITON V-8 AND V-10 ENGINES.ODI RECEIVED A TOTAL OF 474 NON-DUPLICATIVE COMPLAINTS ON THE SUBJECT VEHICLES WHERE THE COMPLAINANT, OR THE DEALER REPAIRING THE VEHICLE, REPORTED THAT A SPARK PLUG DETACHED FROM THE CYLINDER AND/OR EJECTED FROM THE ENGINE.AS OF DECEMBER 8, 2005, ODI IS NOT AWARE OF ANY ALLEGATIONS WHERE THE ALLEGED DEFECT RESULTED IN A LOSS OF VEHICLE CONTROL, A CRASH, AN INJURY, OR A FATALITY IN ANY OF THE 10,319,810 SUBJECT VEHICLES.IN ADDITION, ODI IS AWARE OF ONLY TWO INCIDENTS WHERE THE VEHICLE STALLED WITHOUT RESTART.INFORMATION CONTAINED IN THE ODI CONSUMER COMPLAINTS AND OBTAINED FROM 72 TELEPHONE INTERVIEWS WITH COMPLAINANTS SHOWED THE FOLLOWING:(1) 99% OF THE COMPLAINTS WERE ON MY 1997 TO 2002 SUBJECT VEHICLES.(2) MOST THE COMPLAINANTS REPORTED HEARING A LOUD POP WHILE DRIVING OR UPON STARTING UP THE VEHICLE FOLLOWED BY A LOUD, REPETITIVE CLICKING OR POPPING SOUND.(3) MANY OF THE COMPLAINANTS REPORTED THAT THE POPPING SOUND WAS ACCOMPANIED BY SOME LOSS OF VEHICLE POWER; HOWEVER, IN 99% OF THE INCIDENTS REPORTED, THE VEHICLE DID NOT STALL.IN THE VERY FEW INCIDENTS WHERE THE VEHICLE DID STALL, MOST VEHICLES COULD BE RESTARTED.(4) ONLY A SMALL PERCENTAGE OF THE COMPLAINANTS CITED THAT THEY SMELLED GAS OR A SLIGHT BURNING SMELL WHEN THE INCIDENT OCCURRED.(5) IN ALL BUT A VERY FEW INCIDENTS, VEHICLE DAMAGE WAS LIMITED TO THE ENGINE.IN ONE INCIDENT, THE COMPLAINT REPORTED THAT THE FUEL RAIL WAS DAMAGED AND REPLACED AFTER ONE OF THE SPARK PLUGS EJECTED FROM THE ENGINE; HOWEVER, THE COMPLAINANT REPORTED THAT THE DAMAGE DID NOT RESULT IN ANY TYPE OF FUEL LEAK OR FIRE.IN ANOTHER INCIDENT, THE ONLY INCIDENT WHERE A FIRE WAS ALLEGED, THE COMPLAINANT REPORTED THAT NO FLUID LEAK WAS OBSERVED, BUT THAT A FIRE RESULTED AFTER THE SPARK PLUG HAD EJECTED FROM THE ENGINE AND HE HAD RESTARTED THE VEHICLE AND DRIVEN TO ANOTHER LOCATION.NONE OF THE COMPLAINANTS REPORTED ANY DAMAGE TO THE VEHICLE HOOD.(6) ONLY TWO COMPLAINANTS REPORTED THAT THEY OBSERVED WHAT APPEARED TO BE SOME DROPS OF FUEL COMING FROM THE CYLINDER WHERE THE SPARK PLUG HAD FAILED OR ON THE SPARK PLUG ITSELF; HOWEVER, EACH OF THESE COMPLAINANTS REPORTED THAT THERE WAS NO SMOKE OR FLAMES AS A RESULT OF HIS INCIDENT.AS THE PETITIONER NOTED, AND ODI?S ANALYSIS SHOWED, IT IS POSSIBLE FOR A SPARK PLUG TO DETACH FROM THE ENGINE CYLINDER THREADS IN THE SUBJECT VEHICLES.HOWEVER, ODI?S ANALYSIS OF 474 COMPLAINTS DESCRIBING SUCH INCIDENTS FOUND ONLY A VERY FEW ALLEGED ANY SAFETY-RELATED CONSEQUENCES.NONE OF THESE SHOWED ANY EVIDENCE OF A SERIOUS SAFETY CONSEQUENCE.GIVEN THE LARGE POPULATION AND RELATIVELY LONG EXPOSURE TIME OF THE SUBJECT VEHICLES, THE COMPLAINT ANALYSIS INDICATES THAT THE RISK TO MOTOR VEHICLE SAFETY FROM THE ALLEGED DEFECT IS VERY LOW.IN VIEW OF THE FOREGOING, IT IS UNLIKELY THAT NHTSA WOULD ISSUE AN ORDER FOR THE NOTIFICATION AND REMEDY OF THE ALLEGED DEFECT AT THE CONCLUSION OF THE INVESTIGATION REQUESTED IN THE PETITION.THEREFORE, IN VIEW OF THE NEED TO ALLOCATE AND PRIORITIZE NHTSA?S LIMITED RESOURCES TO BEST ACCOMPLISH THE AGENCY?S SAFETY MISSION, THE PETITION IS DENIED.

Engine And Engine Cooling

ON SEPTEMBER 6, 2005, ODI RECEIVED A PETITION REQUESTING THAT THE AGENCY INVESTIGATE ALLEGATIONS OF ENGINE SPARK PLUG EJECTION IN CERTAIN MODEL YEAR 1997 THROUGH 2004 FORD VEHICLES WITH TRITON V-8 AND V-10 ENGINES.ODI RECEIVED A TOTAL OF 474 NON-DUPLICATIVE COMPLAINTS ON THE SUBJECT VEHICLES WHERE THE COMPLAINANT, OR THE DEALER REPAIRING THE VEHICLE, REPORTED THAT A SPARK PLUG DETACHED FROM THE CYLINDER AND/OR EJECTED FROM THE ENGINE.AS OF DECEMBER 8, 2005, ODI IS NOT AWARE OF ANY ALLEGATIONS WHERE THE ALLEGED DEFECT RESULTED IN A LOSS OF VEHICLE CONTROL, A CRASH, AN INJURY, OR A FATALITY IN ANY OF THE 10,319,810 SUBJECT VEHICLES.IN ADDITION, ODI IS AWARE OF ONLY TWO INCIDENTS WHERE THE VEHICLE STALLED WITHOUT RESTART.INFORMATION CONTAINED IN THE ODI CONSUMER COMPLAINTS AND OBTAINED FROM 72 TELEPHONE INTERVIEWS WITH COMPLAINANTS SHOWED THE FOLLOWING:(1) 99% OF THE COMPLAINTS WERE ON MY 1997 TO 2002 SUBJECT VEHICLES.(2) MOST THE COMPLAINANTS REPORTED HEARING A LOUD POP WHILE DRIVING OR UPON STARTING UP THE VEHICLE FOLLOWED BY A LOUD, REPETITIVE CLICKING OR POPPING SOUND.(3) MANY OF THE COMPLAINANTS REPORTED THAT THE POPPING SOUND WAS ACCOMPANIED BY SOME LOSS OF VEHICLE POWER; HOWEVER, IN 99% OF THE INCIDENTS REPORTED, THE VEHICLE DID NOT STALL.IN THE VERY FEW INCIDENTS WHERE THE VEHICLE DID STALL, MOST VEHICLES COULD BE RESTARTED.(4) ONLY A SMALL PERCENTAGE OF THE COMPLAINANTS CITED THAT THEY SMELLED GAS OR A SLIGHT BURNING SMELL WHEN THE INCIDENT OCCURRED.(5) IN ALL BUT A VERY FEW INCIDENTS, VEHICLE DAMAGE WAS LIMITED TO THE ENGINE.IN ONE INCIDENT, THE COMPLAINT REPORTED THAT THE FUEL RAIL WAS DAMAGED AND REPLACED AFTER ONE OF THE SPARK PLUGS EJECTED FROM THE ENGINE; HOWEVER, THE COMPLAINANT REPORTED THAT THE DAMAGE DID NOT RESULT IN ANY TYPE OF FUEL LEAK OR FIRE.IN ANOTHER INCIDENT, THE ONLY INCIDENT WHERE A FIRE WAS ALLEGED, THE COMPLAINANT REPORTED THAT NO FLUID LEAK WAS OBSERVED, BUT THAT A FIRE RESULTED AFTER THE SPARK PLUG HAD EJECTED FROM THE ENGINE AND HE HAD RESTARTED THE VEHICLE AND DRIVEN TO ANOTHER LOCATION.NONE OF THE COMPLAINANTS REPORTED ANY DAMAGE TO THE VEHICLE HOOD.(6) ONLY TWO COMPLAINANTS REPORTED THAT THEY OBSERVED WHAT APPEARED TO BE SOME DROPS OF FUEL COMING FROM THE CYLINDER WHERE THE SPARK PLUG HAD FAILED OR ON THE SPARK PLUG ITSELF; HOWEVER, EACH OF THESE COMPLAINANTS REPORTED THAT THERE WAS NO SMOKE OR FLAMES AS A RESULT OF HIS INCIDENT.AS THE PETITIONER NOTED, AND ODI?S ANALYSIS SHOWED, IT IS POSSIBLE FOR A SPARK PLUG TO DETACH FROM THE ENGINE CYLINDER THREADS IN THE SUBJECT VEHICLES.HOWEVER, ODI?S ANALYSIS OF 474 COMPLAINTS DESCRIBING SUCH INCIDENTS FOUND ONLY A VERY FEW ALLEGED ANY SAFETY-RELATED CONSEQUENCES.NONE OF THESE SHOWED ANY EVIDENCE OF A SERIOUS SAFETY CONSEQUENCE.GIVEN THE LARGE POPULATION AND RELATIVELY LONG EXPOSURE TIME OF THE SUBJECT VEHICLES, THE COMPLAINT ANALYSIS INDICATES THAT THE RISK TO MOTOR VEHICLE SAFETY FROM THE ALLEGED DEFECT IS VERY LOW.IN VIEW OF THE FOREGOING, IT IS UNLIKELY THAT NHTSA WOULD ISSUE AN ORDER FOR THE NOTIFICATION AND REMEDY OF THE ALLEGED DEFECT AT THE CONCLUSION OF THE INVESTIGATION REQUESTED IN THE PETITION.THEREFORE, IN VIEW OF THE NEED TO ALLOCATE AND PRIORITIZE NHTSA?S LIMITED RESOURCES TO BEST ACCOMPLISH THE AGENCY?S SAFETY MISSION, THE PETITION IS DENIED.