2003 Mercedes-Benz E320 Problems

What owners report

Owners of the 2003 E320 most often report a gasoline smell around and inside the car, usually after refueling, with dealers pointing to the fuel tank, fuel sending unit or fuel lines under the rear seat. A second frequent theme is the Sensotronic (SBC) brake system, where owners describe warning messages and reduced or lost power braking, sometimes after long use. Most reports come in at higher mileage, though some fuel and brake complaints appear well under 60,000 miles.

1. 1
   Fuel system

   Gasoline smell and fuel leaks at tank/sending unit

   • 85 complaints (40%)
   • median 105,000 mi at 11.1 yrs old (67 state mileage)
   • 1 mention a crash, fire or injury
   • owner-quoted repair $3,000 (median of 10 quotes)
   • filed 2010–2024

   Complaints describe a strong gasoline odor inside and outside the car, most noticeable after refueling and sometimes strongest near the rear seat or left rear wheel area. Several owners found liquid fuel pooling under the rear seat cushion, at the fuel sending unit or on top of the tank, and some reported the smell lingering in a garage after parking. Dealers and independent shops variously identified the fuel tank, fuel sending unit, fuel pump neck, fuel filter or fuel lines, and some owners said repairs were quoted but not completed or recurred after replacement. Spread broadly from about 40,000 to over 200,000 miles, with many reports in the 90,000-150,000 mile range, and typically noticed right after filling the tank.

   5 related service bulletins

   What to check: After a fill-up, smell for fuel inside the cabin and under the rear seat, and look for dampness or staining on top of the tank through the access plate. Ask whether the fuel tank, sending unit or pump has been replaced and whether any fuel-system warranty extension still applies.

   2 excerpts from owner complaints in NHTSA records

   “There is a gas leak on the sending unit (fuel tank) when the vehicle is filled with fuel. This is an extremely dangerous issue, and it is common with the mercedes benz E320. I am concerned for my safety and the safety of my child who complains of the strong smell of gas while riding in the car. It leaves the smell of gas in my garage as well..”

   NHTSA complaint #10704053, filed 2015-04, 100 miles

   “There is a strong gasoline smell coming from the car after I filled up at the local gas station. I noticed the smell was very strong in my garage and was able to trace it to my mercedes 2003 E320. It only has 40,000 miles on the odometer and is maintained on a regular basis at my local mercedes dealer.”

   NHTSA complaint #10493645, filed 2013-01, 40,000 miles
2. 2
   Brakes

   SBC brake warning and reduced braking

   • 81 complaints (38%)
   • median 106,000 mi at 11.7 yrs old (63 state mileage)
   • 7 mention a crash, fire or injury
   • owner-quoted repair $2,000 (median of 13 quotes)
   • filed 2003–2024

   Owners describe a red brake warning message telling them to stop driving, a pedal that goes to the floor or needs extra travel, and stopping distances that feel much longer, occasionally with the transmission downshifting or locking. Some say the system returned to normal after restarting or after a short wait, then recurred later. Complaints mention dealers diagnosing the SBC hydraulic unit or ABS pump, sometimes replacing brake sensors or flushing the system, and several note warranty-extension coverage questions around the SBC unit. Reported from very low mileage up to beyond 200,000 miles, with many cases between roughly 50,000 and 150,000 miles, sometimes on the first drive after start-up or under hard braking.

   4 related service bulletins

   What to check: Ask whether the SBC hydraulic unit has been serviced or replaced and whether the extended warranty on it still covers the car. During a test drive, watch for brake warning messages on the cluster and any soft or long pedal.

   2 excerpts from owner complaints in NHTSA records

   “When the car was two months old, 1500 miles, a warning light came on telling me that my brakes may not be working and that I should stop driving immediately. In fact the brakes were not working and I had a hard time stopping on the side of the highway. The car was towed to knauz mercedes in lake bluff. They still have not told me what went wrong but say that they have gotten new parts and the brakes should be fine.”

   NHTSA complaint #10030401, filed 2003-07, 1,500 miles

   “Complete brake failure. Almost crashed. I have numerous fault codes in computer, ABS code, sbc code, resivior code, etc, etc on a 58,000 milr car! They are telling me only one part has extended warranty and that is the sbc. Everything else I must pay for. The sbc effects all of these other parts and that is crap! Like which came first? The chicken or the egg. Why have you not effected a complete recall of this make & model as everyone is having the same problem. …”

   NHTSA complaint #10403336, filed 2011-05, 58,206 miles

Buying note. Budget for a careful fuel-system inspection at the rear seat and tank area, and confirm the brake (SBC) unit's service history and any remaining coverage. A pre-purchase scan for stored codes plus a test drive that includes hard braking and a cold start will surface most of what owners report.

Summary written with AI from a sample of 60 NHTSA complaints for this model year (picked at random, with complaints that state a mileage and recent ones taken first), then checked automatically against the source records. Where a problem shows a complaint count, every complaint for this model year was matched with fixed keyword rules (written with AI and tested against the sample), and the mileage, age and repair figures are calculated from those complaints; owners' figures are as stated, not verified. Other counts refer to the sample. The excerpts come from NHTSA's public complaint records and are unverified; capitalisation is normalised, NHTSA staff notes are removed, and shortened text ends with “…”. Something wrong? Request a correction.