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Hello
I have a 94 xjs that is giving me oxygen sensor problems.
This is only my second summer with this car and like last year, it is indicating an oxygen sensor malfunction. I am wondering what could be causing this because with new sensors, the car runs like a dream, but I don't want to replace them every 2,000 miles.
Would it be caused by the fuel? My manual specs 95 octane, the highest we have is 94. The fuel also has ethanol in it, which probably was not around in 94. Should I just add an octane booster to each tank of fuel?
Any suggestions are greatly appreciated.
Thank you.
David