An investigation means NHTSA has decided a pattern is worth examining. A
preliminary evaluation is often closed with no action; an engineering
analysis is the stage that usually precedes a recall.
Diesel Fuel Injector Line Leakage
PE11023
Closed preliminary evaluation · opened August 2, 2011 · closed December 2, 2011 · led to recall 11V490000
the diesel fuel system
By letter dated October 3, 2011, Volkswagen Group of America, Inc. (VW) notified the National Highway Traffic Safety Administration (NHTSA) that it will conduct a safety recall to address a defect in approximately 168,275 model year (MY) 2009-2012 Volkswagen Jetta, Jetta Sportwagen, Golf, and Audi A3 vehicles equipped with the 2.0L TDI Common Rail Clean Diesel engine (NHTSA Recall No. 11V-490).The recalled Jetta and Jetta Sportwagen vehicles were built from May 2008 through September 2011, the Golf vehicles were built from May 2009 through September 2011, and the Audi A3 vehicles were built from September 2009 through September 2011.According to Volkswagen, in U.S. applications of the above cited TDI vehicles including engine codes CJAA and CBEA, the fuel injection pulses could coincide with the natural frequency of the injector line #2 in specific load and RPM conditions.This resonance creates additional stress on the fuel line which a small number of parts (based on the statistic spread of line strength) cannot withstand over its lifetime.As a contributing factor, VW indicated that a supplier used tube material with scratch marks from a grinding process during certain production periods.Lines manufactured in these periods were installed in vehicles produced in the following 10 months:December 2008, January-February 2009, October 2009, March-April 2010 and September-December 2010.Injector lines using this material exhibit a significantly higher failure rate.Dealers will replace injector line #2 in all vehicles built in these months.In addition, as a precautionary measure, all recalled vehicles will have vibration dampers installed on all four fuel injector lines.Analysis of NHTSA complaints, VW complaints, VW field reports and warranty claims found allegations of injector line leakage in 443 subject vehicles.The leaking line was not identified in 62 of the vehicles.For the 381 that did provide information about which injector lines were leaking and/or replaced, 358 (94%) involved an injector line #2 leak/repair.Almost three-quarters of the injector line #2 leak/repair incident vehicles were built in the 10 months identified by VW, which accounted for approximately one-quarter of the recalled vehicles.The failure rate for injector line #2 in vehicles built in the 10 months affected by the supplier line scratching issue is 6.0 incidents per thousand vehicles (IPTV).The failure rate for injector line #2 in other production months of recalled vehicles is 0.8 IPTV.The leak/repair rates for the other injector lines are all well under 1 IPTV.The action taken by Volkswagen is sufficient to resolve the issues raised by this investigation. The agency will continue to monitor this issue and reserves the right to take further action if warranted by the circumstances. Accordingly, this investigation is closed.
High-Pressure Fuel Pump Failure
EA11003
Closed engineering analysis · opened February 7, 2011 · closed March 27, 2015
the diesel fuel system, the fuel system
The Office of Defects Investgation (ODI) opened EA11-003 on February 7, 2011, based on 160 complaints to ODI and Volkswagen involving high pressure fuel pump (HPFP) failures in model year (MY) 2009 through 2010 Volkswagen Jetta and Golf and Audi A3 TDI vehicles and questions regarding fuel sample results provided by Volkswagen as part of its response to PE10-034.During EA11-003, ODI analyzed design information, field experience and test data for MY 2009 through 2012 Volkswagen Jetta, Golf and Touareg and Audi A3 and Q7 vehicles equipped with TDI engines. Volkswagen has not identified any design or manufacturing defects in the subject TDI Clean Diesel pumps and has stated that the subject pumps were designed, tested and approved for use in the United States market, with substantial design margins for fuels that are out of specification.Volkswagen believes that misfueling with gasoline is the primary cause of HPFP drivetrain failures in the field.Only the Q7 vehicles were built with misfuel protection devices.In May 2013 Volkswagen initiated a service campaign to install misfuel protection devices in all MY 2009 through 2012 Jetta, Golf and A3 vehicles.Volkswagen implemented misfuel protection devices in all of the subject models beginning in MY 2013. ODI?s analysis of HPFP drivetrain failure incidents indicates that most failures do not result in engine stall while driving and, when pump drivetrain failure does result in stall while driving, it is usually preceded by numerous warning symptoms (e.g., glow plug warning lamp, chime, limp mode, and driveability symptoms).The failure data for the subject vehicles show relatively low stalling rates (less than one percent at three years in service) for each of the pump designs used in the subject vehicles.There have been no reports of crashes, injuries or fatalities related to the alleged defect. Based on these facts, this investigation is closed.The closing of this investigation does not constitute a finding by NHTSA that a safety-related defect does not exist.The agency will continue to monitor complaints and other information relating to the alleged defect in the subject vehicles and take further action in the future if warranted.For additional information, see the closing report in the document file for EA11-003.
High Pressure Fuel Pump Failure (HPFP)
PE10034
Closed preliminary evaluation · opened August 26, 2010 · closed February 8, 2011
the diesel fuel system
The Office of Defects Investigation (ODI) and Volkswagen (VW) have received a total of 160 complaints and field reports alleging incidents of engine stall and/or loss of power that appear to be related to high pressure fuel pump (HPFP) failures in certain model year (MY) 2009 through 2010 Volkswagen Jetta and MY 2010 Volkswagen Golf and Audi A3 vehicles equipped with TDI clean diesel engines.Approximately half of the reports indicate that the failure resulted in an engine stall incident, with many of these alleging stall incidents at highway speeds in traffic with no restart.There has been one minor crash alleged to have resulted from HPFP failure in the subject vehicles.In response to ODI's information request for PE10-034, VW indicated that it had found no defect related to motor vehicle safety with relation to the TDI Clean Diesel fuel system at issue in this investigation and attributed problems with HPFP failure to operation with gasoline contaminated diesel fuel.Volkswagen stated that even a small amount of gasoline in the diesel fuel may disrupt the necessary lubrication required and may cause the HPFP to fail.In response to concerns that fuel contamination was the major cause of HPFP and related fuel system failures, VW issued a Technical Service Bulletin in May 2010 (VW TB V011011 2023624 and Audi TB A011008 2023360-1), with instructions to inspect the diesel fuel for vehicles requiring fuel system service that have symptoms associated with HPFP failure.The bulletin states that fuel system damage incurred by use of fuel not complying to ASTM-D-975 Grade 2 S15 (B5 or less biodiesel content) standards will not be covered under warranty. Volkswagen also provided information about 121 mis-fueling incidents reportedly acknowledged by consumers or dealers and test results for about 50 diesel fuel samples taken from complaint vehicles in late-August through early-October 2010.The mis-fueling incidents include about 20 reports involving incorrect fueling by dealer sales or service personnel and generally report symptoms such as rough running, stalling and/or no start within a few miles of refueling the vehicle with gasoline.Volkswagen indicated that the testing of fuel samples from complaint vehicles found that nearly 90 percent contained high amounts of gasoline.Volkswagen implemented design changes for the HPFP in May 2008, September 2009 and November 2010 to improve the robustness of the pump when used with poor quality fuel.ODI analysis of HPFP failures identified from all sources shows failure rates of 0.53% for MY 2009 vehicles and 0.11% for MY 2010 vehicles.This investigation has been upgraded to an Engineering Analysis (EA11-003) to continue to investigate the issues with mis-fueling and HPFP design identified during the Preliminary Evaluation.
VEHICLE STALL/LOSS MOTIVE POWER
PE09035
Closed preliminary evaluation · opened July 17, 2009 · closed November 19, 2009 · led to recall 09V333000
the power train
THE SUBJECT VEHICLES ARE EQUIPPED WITH DIRECT SHIFT GEARBOX (DSG) TRANSMISSIONS, WHICH FEATURE A 6-SPEED AUTOMATIC GEARBOX WITH TWO WET RUNNING CLUTCHES (DUAL CLUTCH) IN WHICH THE CLUTCH MECHANISM AND GEAR CHANGES ARE ELECTROHYDRAULICALLY OPERATED BY A MECHATRONIC CONTROL UNIT.THE DSG MECHATRONIC CONTROLLER INCLUDES EXTENSIVE SELF DIAGNOSTIC FUNCTIONS AND STRATEGIES TO ENSURE SAFE OPERATION AND PREVENT SYSTEM/COMPONENT DAMAGE IN THE EVENT OF COMPONENT FAILURES OR HARSH OPERATING CONDITIONS.THE BASIC HIERARCHY OF FAULT MODES INCLUDES SOME THAT ONLY RESULT IN THE STORAGE OF A DIAGNOSTIC TROUBLE CODE (DTC) AND CAUSE NO LOSS OF FUNCTION, SOME THAT STORE A DTC AND REDUCE VEHICLE OPERATION TO A LIMP HOME MODE, AND SOME THAT STORE A DTC AND CAUSE AN INTERRUPTION OF MOTIVE POWER (I.E., OPEN CLUTCH).THE DRIVER IS ALERTED TO THE LATTER TWO MODES BY THE DASH GEAR POSITION INDICATOR (PRNDS) FLASHING. ONE OF THE CONDITIONS THAT RESULTS IN INTERRUPTION OF MOTIVE POWER IS EXCESS GEARBOX TEMPERATURE.THE SYSTEM INITIALLY RESPONDS TO INCREASED GEARBOX TEMPERATURE BY RAMPING DOWN ENGINE TORQUE.IF THE TEMPERATURE KEEPS RISING THE MECHATRONIC UNIT RESPONDS BY OPENING THE CLUTCH.IN A DEFECT INFORMATION REPORT SUBMITTED TO NHTSA ON AUGUST 20, 2009, VOLKSWAGEN DESCRIBED A POTENTIAL DEFECT IN THE WIRING HARNESSES OF THE DSG GEARBOX TEMPERATURE SENSORS USED IN APPROXIMATELY 16,000 MODEL YEAR (MY) 2009 AND 2010 VOLKSWAGEN (EOS, JETTA AND GTI) AND AUDI (A3 AND TT/TT ROADSTER) VEHICLES EQUIPPED WITH DSG TRANSMISSIONS AND BUILT FROM SEPTEMBER 2008 THROUGH AUGUST 2009 (NHTSA RECALL NO. 09V-333, VOLKSWAGEN RECALL NO. 37E3/S7 AND AUDI RECALL NO 37E4/J7). VOLKSWAGEN PROVIDED THIS DESCRIPTION OF THE DEFECT, THE WIRING HARNESS OF A TEMPERATURE SENSOR IN THE DSG MAY HAVE CONNECTOR WIRES THAT WERE INSUFFICIENTLY CRIMPED BY THE CONNECTOR SUPPLIER DURING A LIMITED PRODUCTION PERIOD.WITH INSUFFICIENTLY CRIMPED CONNECTOR WIRES, A TEMPERATURE SENSOR HAS THE POTENTIAL TO FALSELY DETECT A HIGH GEARBOX OIL TEMPERATURE, CAUSING THE TRANSMISSION TO ABRUPTLY SHIFT TO NEUTRAL.IF THIS HAPPENS, THE SELECTOR LEVER POSITION INDICATOR WITHIN THE INSTRUMENT PANEL WILL FLASH.IN ADDITION, THE DEPRESS BRAKE PEDAL INDICATOR LIGHT WILL BE ILLUMINATED, ALERTING THE DRIVER TO APPLY THE BRAKES.IN HEAVY TRAFFIC, THE ABRUPT SHIFT TO NEUTRAL COULD LEAD TO A CRASH WITHOUT WARNING.VOLKSWAGEN ESTIMATED THAT LESS THAN ONE PERCENT OF THE RECALLED VEHICLES MAY CONTAIN THE DEFECT CONDITION. ODI IDENTIFIED 40 COMPLAINTS THAT APPEAR TO BE RELATED TO THE TEMPERATURE SENSOR DEFECT CONDITION DESCRIBED BY VOLKSWAGEN.VOLKSWAGEN RECEIVED 139 COMPLAINTS RELATED TO THE CONDITION, WITH 7 INVOLVING VEHICLES REPORTED TO ODI, RESULTING A 172 TOTAL COMPLAINTS TO ODI AND VOLKSWAGEN.ALL OF THESE COMPLAINTS INVOLVE THE MY 2009 AN 2010 VEHICLES SUBJECT TO RECALL 09V-333. ODI ALSO IDENTIFIED COMPLAINTS OF HARSH/JERKY SHIFTING IN SOME VOLKSWAGEN VEHICLES WITH DSG.VOLKSWAGEN ATTRIBUTED THIS CONDITION, WHICH TYPICALLY OCCURS AT VERY LOW SPEEDS, TO EXCESSIVE WEAR IN THE BUSHINGS OF THE TWO SOLENOID VALVES IN THE MECHATRONIC UNIT THAT CONTROL CLUTCH OPERATION.VOLKSWAGEN DOES NOT BELIEVE THAT THE THIS CONDITION IS A SAFETY DEFECT BECAUSE THE CHANGES IN SHIFT QUALITY DEVELOP GRADUALLY OVER TIME, DO NOT CAUSE A LOSS OF MOTIVE POWER AND HAVE NOT RESULTED IN ANY FATALITIES, INJURIES OR SERIOUS CRASHES (THERE WERE THREE REPORTED PROPERTY DAMAGE INCIDENTS RESULTING IN MINOR BODY DAMAGE IN VERY LOW SPEED, PARKING MANEUVERS).VOLKSWAGEN ADDRESSED THIS PROBLEM IN THE FIELD WITH A CUSTOMER SERVICE PROGRAM THAT INCLUDES THE REPLACEMENT OF POTENTIALLY AFFECTED MECHATRONIC UNITS AS WELL