Popped a P0 452 and 449 code, replaced the charcoal canister, fuel pressure sensor and all related parts but the check engine light is still on. Is there a sequence youhave to go thru to clear the codes?

 

Anytime you get a sensor code (including in this case), all you know is that the system using that sensor believes that something is out of bounds. You don't yet know if the sensor has reported a proper value telling you that something has failed or the sensor is faulty and not reporting correctly. It could be (PO452):

The sensor is faulty
The wiring/connectors are bad
PCM trouble
Voltage or ground issues
Mechanical system leak in vent lines, gas tank, cap, etc
Faulty evap solenoid
Faulty purge solenoid
...

If the problem has been corrected then the MIL will reset after the next round of system tests, unless the PCM is faulty.


George