I have a 2001 Accent and the horsepower is severly declining. Sometimes when I am driving up a hill the engine seems to rev very low and then it seems like it jumps. I'm not sure what is causing this but my mechanic told me to replace the fuel sensor. I knowvery littleabout cars and if someone knows what would cause this and what to repair please let me know.

 

I'm not aware of a particular sensor called the "fuel sensor", but there are many sensors associated with the fuel management system. Which engine does the car have? Is the check engine light on? When the mechanic diagnosed the "fuel sensor" problem. did he say if any error codes were scanned from the car's computer system?

 

I'm sorry I meant to say the oxygen sensor not the "fuel sensor" This is the only error that he came up with while running it on the computer.

 

The oxygen sensors (I think there are a pair on this car) are part of the fuel management sysem. They are mounted in the exhaust system to measure how complete the fuel has been combusted in the cylinders of the engine. Feedback from these sensors helps the engine control module determine the optimum fuel/air ratio that is needed by theengine at any particular moment. Because the oxygen sensors are mounted into the exhaust stream, they are exposed to extremely high temperatures, hot corrosive gases and somtimes too much moisture. Consequently, they wear out and it's not unusual to have these replaced at least once during the life of a car. If your mechanic says he has pulled error codes indicating bad oxygen sensors, they need to be replaced.