I had a carbon blaster treatment and o2 sensors changed in my 98 E320 w/
62,000 miles on the clock the CE light was on and the codes said banks 1 &
2. I saw the removed units, they were torched.
My independent wrench warned the previous owner used cheap gas, which
smoked the sensors and filled the engine with carbon. He warned that the
cats may be spoiled. He won't be sure for a few days, until the computer
does a drive cycle. To help clear things, took it last night for a 45 min
blowout on the highway.
Question: If the cats are gone, because of bad gas or some other
non-physical damage, are they covered under warranty? Anyone with
experience on this claim at a dealership?
Thanks in advance for your responses.