Ive replaced the sensor already but its the heater circuit thats the issue :/ break in the wires somewhere.

The car has a scorpion cat back and a k & n filter so its pretty much standard. I dont want massive power gains, just want a nicer driving car. Not going to pour massive money into it. Will pedley has done some amazing things with a 170 and cat cams do a decent upgrade but it means after market ecus etc and i dont want to do anything to serious