NHTSA Office of Defects Investigation
Engineering Analysis EA13-003: Fuel Leakage From The Fuel Tank
- Closed
NHTSA's Office of Defects Investigation opened Engineering Analysis EA13-003 on March 15, 2013 and closed it on December 19, 2014. NHTSA's investigations file lists 6 Mercedes Benz models for it.
Updated daily from NHTSA's investigations file
Key facts
- NHTSA number
- EA13-003 (also written EA13003)
- Investigation type
- Engineering Analysis A more detailed stage of a defect investigation, opened when NHTSA's Office of Defects Investigation decides an issue merits further review, often after a Preliminary Evaluation or a Recall Query; it can include vehicle testing, surveys and further information requests.
- Status
- Closed December 19, 2014
- Opened
- Closed
- Vehicle or equipment manufacturer
- Mercedes-Benz USA, LLC
- Components
- Fuel System, Gasoline; Fuel System, Gasoline — Delivery; Fuel System, Gasoline — Delivery — Fuel Pump; Fuel System, Gasoline — Delivery — Hoses, Lines/Piping, and Fittings; Fuel System, Gasoline — Storage; Fuel System, Gasoline — Storage — Tank Assembly
- Vehicles and equipment
- 6 Mercedes Benz models, including the AMG E55 and E500
A recall appears here only when NHTSA's investigations file links one to the investigation; NHTSA's summary or record can name others.
NHTSA's summary
As NHTSA's Office of Defects Investigation wrote it for Engineering Analysis EA13-003.
try.vin does not copy NHTSA's investigation documents; NHTSA's investigation record lists the ones NHTSA has published.
The Office of Defects Investigation (ODI) opened this investigation on January 23, 2012 as PE12-001 based on 20 consumer reports in model year (MY) 2003-2006 E55 AMG vehicles.
Based on new reports in other E-Class vehicles, ODI upgraded the investigation to Engineering Analysis (EA) 13-003 on March 15, 2013, and expanded the scope to all E-Class vehicles through MY 2008.
The complainants alleged a strong odor of gasoline fuel both inside and outside of their vehicle, particularly after refilling the fuel tank.
Many of the complainants noted that the odor subsided or went away after driving some distance thereby lowering the fuel level in the tank.
Other owners reported they would only fill the tank to about three quarters full to avoid the odor altogether.
Some complainants alleged fuel leaked from the fuel filter/sender, located on the top of the fuel tank on the driver's side, and collected on top of the tank.
There were also allegations that the fuel leaks were associated with an Emissions Recall Campaign (No. 2008020001) conducted by Mercedes-Benz USA, LLC (Mercedes) in 2008 on MY 2003-2006 E-Class and CLS-Class AMG models.
The issue in the recall involved small cracks in the pressurized outlet fitting of the fuel filter/sender.
AMG vehicles are high performance models that operate at higher fuel pressure and use a different fuel filter/sender and fuel pump than non-AMG models.
Information on Recall No. 2008020001 is available from the U.S. Environmental Protection Agency (EPA) website at www.EPA.gov.
ODI's investigation found various leak sources that are unrelated to the outlet fitting cited in the EPA recall campaign.
Through interviews with complainants, field inspections of complaint vehicles, and the collection and laboratory analysis of failed parts, three identifiable leak sources were found.
The component parts and areas of the leaks involve the On-Board Diagnostic fuel tank pressure sensor (located on top of the fuel filter/sender), the outlet of the centrally mounted fuel tank fuel filling limiter valve, and the top of the fuel pump. These areas of leakage are located at the top of the fuel tank in unpressurized parts of the fuel system. When the tank is full, fuel can slowly weep/seep from micro-cracks in these components and may collect in cavities on top of the filter/sender, pump, or tank.
Contrary to complainant's allegations that fuel entered the inside of their vehicle under the rear seat bench, neither ODI nor Mercedes found a plausible way for this to occur.
The fuel tank is located outside of the passenger compartment, attached to the underside of the vehicle.
The service access ports for the fuel filter/sender (driver's side) and fuel pump (passenger's side) are located under the rear seat bench, covered by a steel plate, sealed and bolted to the vehicle floor.
When technicians service the fuel filter/sender, which has a regularly scheduled 60,000 mile service interval, and/or the fuel pump, the work is performed from inside the vehicle by working through the access ports.
By letter dated September 4, 2014, Mercedes has notified the agency that it will extend the original warranty coverage to 15 years and unlimited mileage on Covered Fuel Tank Components in E-Class vehicles in MY 2003-2009 and CLS-Class vehicles in MY 2006-2011.
The covered fuel tank components for the warranty extension include the fuel tank, fuel filter/sender, fuel pump, and all related gaskets/seals and retention rings.
ODI is closing this investigation based on the manufacturer's extend warranty of the affected fuel system components and in consideration that the nature of the leaks does not appear to present an un
Vehicles and equipment listed for this investigation
NHTSA's investigations file lists these vehicles and equipment for Engineering Analysis EA13-003. A listed model year means only that an investigation names it; it says nothing about any particular vehicle. Model years with a try.vin recall page link to that page's NHTSA investigations section.
What an NHTSA investigation is
NHTSA's Office of Defects Investigation (ODI) looks into possible safety defects in vehicles and equipment, often after owner complaints. An investigation usually starts as a Preliminary Evaluation, or as a Recall Query when it concerns whether an existing recall covers the right vehicles or fixes the problem, and ODI can upgrade it to a more detailed Engineering Analysis. A Defect Petition asks NHTSA to open an investigation, and Audit and Equipment Queries are administrative investigations into whether companies complied with federal vehicle safety requirements, such as reporting, recall and certification rules.
An open investigation is not a finding that a safety defect exists, and NHTSA can close one without a recall.
To see whether a specific vehicle has an open recall, enter its VIN at nhtsa.gov/recalls.
Mercedes Benz VIN check: decode a VIN to see its year, make and model.
Sources
NHTSA's investigation record for EA13-003
Investigation details come from NHTSA's investigations file, which try.vin imports once a day. The investigation types are described from the U.S. Department of Transportation Inspector General's May 2023 report on NHTSA's Office of Defects Investigation, NHTSA's petition rules (49 CFR Parts 552 and 557) and NHTSA's Office of Defects Investigation procedures. How try.vin reads NHTSA investigations.