2000 Buick LeSabre

There are a few things to check.....you have the 3800 V6 engine which is a great motor. If the CAM sensor is bad the gas mileage and performance will suffer. The most common problem is not that the sensor is bad but the magnet on the cam that triggers the sensor has fallen out of its plastic holder. If you are a DIY person, pull the passanger front wheel and then remove the cam sensor (easy to get to with the wheel removerd) With the sensor out, turn the engine until you can see where the magnet fits in the end of the cam. If there is just a hole, then the plastic has failed and the magnet has come out. Most auto parts stores carry the magnet and holder.......if the magnet is there, you can replace the sensor to see if that fixes the problem. Another sensor that can fail is the "KNOCK SENSOR" ....as the name implies, it sensor engine knock and retarts the timing, which affects gas mileage and performance. Very easy to replace, just screws in.