Po 1447 evap system - 1997 Nissan Pathfinder

No these are 2 different fault codes, although they are related to the same system
EVAP control system does not operate properly.
- EVAP control system has a leak in the line between intake manifold and EVAP control system pressure sensor.

Possible causes include ...
- EVAP canister purge volume control solenoid valve stuck closed.
- EVAP control system pressure sensor and its circuit.
- Loose, disconnected, or improper connection of rubber tube.
- Blocked rubber tube.
- Blocked or bent rubber tube to MAP/BARO switch solenoid valve.
- Cracked EVAP canister.
- EVAP canister purge volume control solenoid valve.
- Closed Throttle Position Switch.
- Improper connection of one-way valve.
- Blocked purge port.
- EVAP canister vent control valve.

The codes only tell the mechanic what to test, not what to replace.
You would need to get the shop manual for your vehicle to have the test instructions for each code.
Code 452 is a problem with the fuel tank pressure sensor circuit, 443 is evap canister purge and 449 is the vent valve circuit.
The evap system and those components would need to be checked out.

The PO 442 code is an EVAP system small leak, either in the evaporative system or cooling. Sometimes this will occur after a drenching rain and remain until the diagnosis code is reset, usually will disappear after you read the codes. If not, a dealer can reset the code system via the radio believe it or not. PO 445 is similar, an EVAP system code but is usually related to gas vapors being sent to the engine rather than through the atmospheric venting system. Check the gas cap system here first, a gas cap not properly tightened (3 click) will sometimes cause this. Also, look to the spark system wiring harness or purge control solenoid.

Trouble Code: P0128

Thermostat Rationality Test

Possible Causes:


Check the operation of the thermostat (it may be stuck open).ECT Sensor is contaminated, damaged or it has failed.Inspect for low coolant level or for an incorrect coolant mixture.Trouble Code: P0440

EVAP Purge System Fault

Possible Causes:


EVAP purge valve vacuum supply is leaking or clogged.EVAP purge valve is stuck closed.EVAP purge solenoid has failed.NVLD assembly (leak detection) is damaged or has failed.NVLD switch circuit is open or the NVLD switch has failed.Ground circuit is open.PCM has failed.Trouble Code: P0456

EVAP Small Leak (0.020") Detected

Possible Causes:


.EVAP fuel tank or canister vapor hoses leaking or damaged.EVAP system component leaking, fuel cap loose or missing.Leak detection pump damaged or leaking.Trouble Code: P0622

Generator Field Control Circuit Malfunction

Possible Causes:


Generator field control circuit is open or is shorted to ground.Generator field control circuit is shorted to system power (B+).Generator field ground circuit is open.Generator is damaged or PCM has failed.PCM has failed.Here are the codes and causes.

I would guess you have not started your search yet

I put OBD2 1447 into explorer & you can read for hours

You can do that with all Generic PO Codes

You can do that for any codes,what you can not do
is get manufacture codes out of the vehicle, without
professional scan tool software

You can look them up generic & Mfg, but only get
generic PO Codes with a code reader,the free stuff
at the parts store

NOPE CANT ERASE CODES UNTIL THE PROBLEM IS FIXED OR THE SERVICE ENGINE LIGHT SOON WILL STAY ON. CODE PO441 - EVAPORATIVE EMISSION EVAP SYSTEM INCORRECT FLOW DETECTED.CHECK INTAKE VACUUM HOSE CONNECTIONS AT THE EVAP CANISTER PURGE VALVE.IF ALL IS GOOD.THE EVAP CANISTER PURGE VALVE COULD BE BAD. CODE PO 442 - EVAPORATIVE EMISSION EVAP SYSTEM SMALL LEAK DETECTED. EVAPORATIVE EMISSION SYSTEM LARGE LEAK DETECTED FUEL CAP LOOSE OR OFF MISSING. CODE PO 446 - EVAPORATIVE EMISSION EVAP SYSTEM VENT CONTROL CIRCUIT MALFUNCTION.

PO 301 is no 1 cylinder misfire, PO 410 is secondary air injection system, & PO 442 is Medium leak detected in EVAP system.

P0341-Camshaft position sensor malfunction.P0440-Evaporative emission system/EVAP/ malfunction.Check for air leak,hoses.If O.K. change EVAP canister purge valve.

Ford: EVAP System Purge Flow Monitor maffunction.

EVAP is for Evaporative emissions control system, so no this is not EGR, that is Exhaust Gas Recirculation system, as far as the P1665 goes it is related to the other trouble code P0440, u will need to replace the EVAP system Purge flow control solenoid. This should correct both problems after u replace the part disconnect the battery for 5 min's to reset system.