The problem may have been caused by a previous recall "fix."
As many as 250,000 Mercedes-Benz E-Class luxury cars are being targeted by an expanded federal safety probe.
The National Highway Traffic Safety Administration is working with the German maker to see if fuel might leak from the upper part of the gas tank in the luxury cars – a problem that might inadvertently have been caused by repairs made during a previous recall.
NHTSA and Mercedes have so far received about 533 complaints from owners claiming to smell a strong odor of gasoline, usually after refueling.
“We are taking this topic seriously and are cooperating with NHTSA,” Mercedes said in a statement. “Neither we nor NHTSA have received any reports of fire, accidents, or injury.”
An engineering analysis is now underway and could eventually lead to a recall of E-Class models produced between the 2003 and 2008 model-years. There are some indications that the problem may have been the inadvertent result of repairs made to solve another problem, a 2008 recall to fix the E-Class pollution control system.
The investigation initially focused on a small number of high-performance Mercedes E55 AMG models produced between 2003 and 2006. About 20 complaints involving the low-volume model were received. But the probe has been expanded to also involve E320, E350, E500, EA550 and E63 AMG models.
Nearly 6,000 Mercedes vehicles involving eight different models were involved in a recall last December due to a potential fire risk. That safety action was caused by a faulty fuel filler flange that could crack and spill gasoline during refueling.
A who’s-who of automaker have faced recalls due to fuel spill and other fire related problems over the last year. These range from the 2013 Ford Escape, where a fuel line could split and leak gas, to a wide range of Toyota products equipped with a faulty power window switch that could overheat and cause a fire.