hi guys, my cars thrown up a fault code relating to the fuel cap sensor, i.e. to do with the god forsaken dpf system. my question is can u buy only the sensor or do u have to buy the whole wiring harness aswell??? went into peugeot tday and they say ive to buy the whole harness for £69 sheets but ive heard of people on here replacing there cap sensor for only £20. im confused.