Check engine light came on (code P0138) but disappeared a day later. on 2007 Toyota Corolla

Few months ago due to recall and check engine light the ECM control was replaced by the dealership. Two days ago check engine light came on; when checked it showed the code P0138 but the light disappeared a day later. Please help me with this.

by in West Hempstead, NY on August 01, 2011
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3 answers
ANSWER by , August 01, 2011
Take it back to the dealership and tell them about the problem, maybe the computer-re-flash did not go well.
ANSWER by , August 02, 2011
for this code, you can try this Replace O2 sensor. Repair short to battery voltage in o2 sensor signal circuit.
ANSWER by , August 02, 2011
Hello i would go back to the dealer right away and have them recheck the recall work performed and the re-programing of the computer.HAVE A BLESS DAY from DR.RECO.