One problem related to fuel hoses lines/piping and fittings has been reported for the 2003 Lexus ES. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2003 Lexus ES based on all problems reported for the 2003 ES.
Fuel line ruptured (part number 23801-20150 pipe sub assembly). Fuel was splashing all over the engine compartment and fumes were pouring into the passenger cabin causing nausea. I was able to pull into a work shop where the problem was diagnosed and we could see fuel splashing when the engine was on. I contacted the Lexus dealer who dosent keep the part in stock and wouldnt comment on the problem nor provide any assistance to diagnose or advise cause of the problem.