I have a 96 Mercury Sable. Recently drove it 1200 miles when I moved to Florida from Indiana. This is my second week here and yesterday the check engine light came on. Took it to shop and they obtained the following problem: P0135 B1 s1, P0141 B1 s2, P0155 B2 S1, P0161 B2 S2. They reset it and it did come back on right after I drove. What kind of cost am I looking at and what exactly needs repaired? I am having problems with the RPM's going up sometimes when I accelerate. The shop said that since I was at so many different gas stations on my long drive that I could have accidentally used a low octaine--ethanol by accident. I have not let my gas get low enough so if that is the case, I am trying now to get it almost completely empty. They said all four sensors going off at once is very strange. What do you suggest I do from here. I am worried and want to get it taken care of.

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1996 Mercury Sable V6

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