I recently got the code P0340 for the camshaft position sensor. I replaced the sensor but did not take the camshaft position magnet off and then put it back on like the manual said because I figured if I wasn't replacing the magnet then it should already still be lined up correctly. I noticed that after changing the camshaft position sensor, I get worse gas mileage than I did before I changed it. Could this be a result of me not taking the camshaft position magnet off and putting it back on like the manual says, or is it something else? Is it absolutely necessary to take the magnet off and put it back on when changing the sensor? I would appreciate any feedback I can get. Thank you.

 

It shouldn't really affect your mileage, it has been warmer the last few days so if you are running your A/C, you will be burning more fuel for sure.

 

I know I will use more gas by using the a/c but I am talking about going from about 125 to 150 miles for the first half a tank to about 75 miles for the first half a tank after changing the part. Something had to have went wrong I am thinking.