IllustrationPROBLEM WITH THE AIR SUSPENSION ON VEHICLE. HAD IT REPLACE WITH LESS THAN 50 THOUSAND MILES ON VEHICLE, ADDED 12 THOUSAND MILES IN LESS THAN A YEAR AND THE AIR SUSPENSION IS OUT AGAIN. *TR
2004 Lincoln Navigator
Owner reports · Recalls · Investigations
Similar to other model years
Owner complaints for the 2004 Lincoln Navigator do not stand out strongly from the model-year median of 30.
About this comparison →How this year compares
Owner complaints by model year
Compare all Navigator years →Counts vary with age, sales and reporting. They are not failure rates.
What owners reported most
All reported categories
Tap a category to read its complaints. One report may name several components.
When problems were reported
Mileage at the reported incident
180–25K
525–50K
1150–75K
1175–100K
11100–150K
6150K+
62 reports with mileage · 24 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 24 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
- Air Bags. Review the 13 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
- Electrical System. Review the 11 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
NHTSA owner reports · September 18, 2026 snapshot.
4 crash reports2 fire reports5 injury reports
Suspension complaints
24 reportsTL*THE CONTACT OWNS A 2004 LINCOLN NAVIGATOR. AFTER THE VEHICLE WAS PURCHASED, IT BEGAN TO FAIL. THE VEHICLE WAS TAKEN BACK TO THE DEALER FOR REPAIRS. ONE MONTH LATER, THE SUSPENSION FAILED. WHILE DRIVING AT AN UNKNOWN SPEED, THE TRAC INDICATOR ILLUMINATED AND THE CONTACT LOST CONTROL OF THE VEHICLE. SHE PULLED OVER AND HAD…
Read full complaint
TL*THE CONTACT OWNS A 2004 LINCOLN NAVIGATOR. AFTER THE VEHICLE WAS PURCHASED, IT BEGAN TO FAIL. THE VEHICLE WAS TAKEN BACK TO THE DEALER FOR REPAIRS. ONE MONTH LATER, THE SUSPENSION FAILED. WHILE DRIVING AT AN UNKNOWN SPEED, THE TRAC INDICATOR ILLUMINATED AND THE CONTACT LOST CONTROL OF THE VEHICLE. SHE PULLED OVER AND HAD THE VEHICLE TOWED TO THE DEALER. THE VEHICLE WAS REPAIRED FOR FREE. AFTERWARDS, THE LOW BEAM HEADLIGHTS FAILED AND THE CONTACT REPLACED THEM WITH TWO BULB MECHANISMS. THE LOW BEAMS CONTINUED TO FAIL AND THE MECHANIC COULD NOT FIND ANY FAILURES. THE DEALER STATED THAT THE WIRING WAS NOT FAULTY, BUT THEY DISCOVERED THAT THE BALLETS IN THE LOW BEAMS WERE BLOWN OUT. THE PARTS WERE ORDERED AND REPLACED BY A MECHANIC. THE BULBS BLEW OUT AGAIN WITHIN A MONTH. THE VEHICLE WAS TAKEN BACK TO THE DEALER AND THEY KEPT IT OVERNIGHT TO REPAIR IT AGAIN. THROUGH ONLINE RESEARCH, THE CONTACT FOUND COMPLAINTS FOR FAILED BALLETS ON HIS MAKE AND MODEL VEHICLE. NO ONE HAS BEEN ABLE TO DETERMINE THE CAUSE OF THE FAILURE. THE FAILURE MILEAGE WAS 75,000 AND CURRENT MILEAGE WAS 98,000.
PROBLEM WITH AIR SUSPENSION ON VEHICLE. PLACED IN SHOP OVER 7 OR MORE TIMES PROBLEM STILL NOT RESOLVED. DEALERSHIP HAS REPLACED PARTS BUT STILL SAME PROBLEM. *TR
WHILE DRIVING THE VEHICLE WOULD VIBRATE. A LOUD BANGING NOISE WAS ALSO HEARD COMING FROM THE DRIVER SIDE WHEEL. THE DRIVER DROVE THE VEHICLE TO THE DEALER FOR INSPECTION. THE MECHANIC PLACED THE VEHICLE ON A DIAGNOSTIC MACHINE BUT COULD NOT DUPLICATE THE PROBLEM. *NM
Official recalls
0No 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
1DP05005 · 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.