I have a 95 F-150, 5.0, automatic, 4wd, with 87,000 miles.

I can drive the truck around town all day with out a single problem in the world runs strong drives great. As soon as i take it for a run down the highway for an extended period of time I get a CEL and if you keep driving the truck the oxygen sensor will eventually fail and the truck will hesitate and lack power idle really rough and have a fuel smell to it. The only way I have been able to get it to run right is by throwing in a new oxygen sensor and it runs like a champ.

I have noticed that if I pull off the highway and drive the truck like I stole it around town the hesitation will go away until I drive the truck on the highway.

I have only been able to do fuel milage once since I have only had the truck about a month and I am only getting about 12.

So what should I check the would keep causing my oxygen sensor to give false readings after being driven down the highway?

here is a link to the code i am getting