Engine light on Codes show 1. Po 441 evaporation emission system incorrect purge flow 2. Po442 evap emission system leak (small) 2. 446 evap emission system incorrect purse flow 2004 Toyota Tacoma pickup 4 cylinder eng.

Check the purge solenoid under the hood common problem in mazda 5 6 cx7.

Error Code: P0440
Fault Location:
Evaporative Emission (EVAP) System - Malfunction
Possible Cause:
Malfunction Indicator Lamp (MIL) active.
Soution:
Check Evaporative Emission (EVAP) System Sealing.
Check Evaporative Emission (EVAP) Canister Purge Regulator Valve .
Check Evaporative Emission (EVAP) Canister Purge Solenoid Valve .

Error Code: P0441
Fault Location:
Evaporative Emission (EVAP) System - Incorrect Flow Detected
Possible Solutions:
Check Evaporative Emission (EVAP) Canister Purge Regulator Valve .
Perform Output Test.
Check Evaporative Emission (EVAP) Canister Purge Solenoid Valve .
Check Evaporative Emission (EVAP) Canister.
Perform Basic Setting.
Check Pipes between Tank Breathing and Throttle Body.

Error Code: P0446
Fault Location:
Evaporative Emission (EVAP) System, Vent Control - Circuit Malfunction
Possible Cause:
Wiring harness.
Evaporative emission (EVAP) canister purge valve.
Engine control module (ECM).

http://www.autozone.com/autozone/repairinfo/repairguide/repairGuideContent.jsp?pageId=0996b43f80380329#hd1-1-28 Here is what is listed for problems,couldn't find codePO446,click on link to view.

440 Evaporative Emission Control System
441 Evaporative Emission System Incorrect Purge Flow
446 Charcoal Canister

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.

Most of the time they mean:
p0441 = Evaporative Emission System Incorrect Purge Flow
p0422 = Evaporative Emission Control System Leak Detected (small leak)

MOre info at http://www.obd-codes.com/p0442

Error Code: P0441
Fault Location:
Evaporative Emission (EVAP) System - Incorrect Flow Detected
Possible Cause:
Malfunction Indicator Lamp (MIL) active.
Evaporative Emission (EVAP) Canister Purge Regulator Valve faulty/jammed.
Evaporative Emission (EVAP) Canister Purge Solenoid Valve faulty/jammed.
Evaporative Emission (EVAP) Canister Sealing faulty.
Pipes between Tank Breathing and Throttle Body leaky/blocked.
Hose connection(s).
Intake leak.
Possible Solutions:
Check Evaporative Emission (EVAP) Canister Purge Regulator Valve .
Perform Output Test.
Check Evaporative Emission (EVAP) Canister Purge Solenoid Valve.
Check Evaporative Emission (EVAP) Canister.
Perform Basic Setting.
Check Pipes between Tank Breathing and Throttle Body.
VSV connector near air filter box disconnected.

P0441 Evaporative Emission Control System Incorrect Purge Flow
P0446 Evaporative Emission Control System Vent Control Circuit Malfunction
P0455 Evaporative Emission Control System Leak Detected (Gross Leak)
http://www.toyotanation.com/forum/showthread.php?t=128923

THESE ARE FROM THE GM CODE DIFINITION MANUAL, U NEED TO TAKE THIS TO THE DELAER, U HAVE SOME SERIOUS PROBLEMS TO GIVE THIS MANY CODES.

P0300 - Engine Random Misfire Detected
P0441 - Evaporative Emission Control System Incorrect Purge Flow
P0705 - Trans Range Switch Circuit
P1106 - Manifold Absolute Pressure (MAP) Sensor Circuit Intermittent High Voltage
P1133 - Heated Oxygen Sensor (HO2S) Insufficient Switching Bank 1 Sensor 1
P1441 - Evaporative Emission (EVAP) System Flow During Non-Purge
P1662 - Cruise Lamp Control Circuit
P1672 - Low Engine Oil Level Lamp Control Circuit
P1870 - Transmission Component Slipping