i had my light on and mechanic gave me two codes- 155 (heater) & 325 (knock sensor). Being a holiday in NY, the store was closed so he could not get the sensor... so i guess he reset the code... now, the light has not come back since then... does that mean that it was a fluke or do the sensors still need to be replaced?

 

No you still need to replace the parts, once the ECU goes through it cycle is will detect the flaws and throw the codes at you again.

 

how long is the cycle?
thanks

 

it should complete its cycle in about 200 miles. I know seem like a lot.