Evaporative Emission Control System Purge Control Valve Circuit Opeat's your problem?

P0443 FORD - EVAP Purge Control Circuit Possible causes Faulty Evaporative Emission (EVAP) Purge Solenoid Control Evaporative Emission (EVAP) Purge Solenoid Control harness is open or shorted Evaporative Emission (EVAP) Purge Solenoid Control circuit poor electrical connection What does this mean? When is the code detected? - An improper voltage signal is sent to ECM through the valve. Possible symptoms Engine Light ON (or Service Engine Soon Warning Light) P0443 Ford Description The Evaporative Emission System (EVAP) canister purge volume control solenoid valve uses a ON/OFF duty to control the flow rate of fuel vapor from the EVAP canister. The EVAP canister purge volume control solenoid valve is moved by ON/OFF pulses from the ECM. The longer the ON pulse, the greater the amount of fuel vapor that will flow through the valve.

A purge control valve circuit open.

P0444, Evaporative Emission System Purge Control Valve Circuit Open". I believe this (small) valve is located underneath the intake manifold behind the oil filter housing. Since there are other codes that indicate leaks in the evap system, you might have to replace the PCV, P0604 could be the coolant level, or a stuck thermostat, top up the coolant, or replace thermostat would be advisable.
hope tis helps

without knowing your make or model:

p1443
Evaporative Emission Control System Control Valve

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EGR Valve Position Sensor Signal Too Low

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Leakage Diagnostic Pump Control Circuit Signal High

ford
EVAP Control System Purge Control Solenoid or Purge Control Valve Fault

hyundi
EVAP System Tank Cap Missing

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Evaporative Emission Control System Control Valve

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Secondary Air Injection Vacuum Switching Valve Circuit Malfunction Bank 2

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Evaporative Emission Control System Large leak detected

mitsubishi
EVAP Purge Control Valve 2 Circuit Malfunction

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Evaporative Emission Control System Vent Control Function Problem

suzuki
EVAP Purge Control Valve Malfunction- Stuck Open

toyota
Secondary Air Injection Vacuum Switching Valve Circuit Malfunction Bank 2

volkswagon
EGR Valve Position Sensor Signal Too Low

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).

Well there is no one thing that causes this fault code but here are what can trigger the fault in the fuel vapor control system.
P0443 FORD - EVAP Purge Control Circuit
Possible causes- Evaporative Emission (EVAP) Purge Solenoid Control harness is open or shorted
- Evaporative Emission (EVAP) Purge Solenoid Control circuit poor electrical connection
- Faulty Evaporative Emission (EVAP) Purge Solenoid Control

Which code specifically? Do not assume you need a new solenoid. Our recommendation will depend on the specific code and some troubleshooting results. I usually recommend checking over all the EVAP vacuum lines and the gas cap too whenever there is a purge valve code. Check the vacuum lines at the cannister in the left rear bumper. I will paste info on the purge solenoid below.

P0440 Evaporative emission (EVAP) system - malfunction

Possible causes: Hose connection(s), intake leak, EVAP canister purge valve

P0441 Evaporative emission (EVAP) system - incorrect flow detected

Possible causes: Hose connection(s), intake leak, EVAP canister purge valve

P0442 Evaporative emission (EVAP) system - small leak detected

Possible causes: Hose connection(s), intake leak, EVAP canister, EVAP canister purge valve

P0443 Evaporative emission (EVAP) canister purge valve - circuit malfunction

Possible causes: Wiring, EVAP canister purge valve, ECM

P0444 Evaporative emission (EVAP) canister purge valve -open circuit

Possible causes: Wiring open circuit, EVAP canister purge valve, ECM

P0445 Evaporative emission (EVAP) canister purge valve -short circuit

Possible causes: Wiring short circuit, EVAP canister purge valve, ECM

P0450 Evaporative emission (EVAP) pressure sensor - circuit malfunction

Possible causes: Wiring, EVAP pressure sensor, ECM

P0455 Evaporative emission (EVAP) system - large leak detected

Possible causes: Hose connection(s), intake leak, EVAP canister, EVAP canister purge valve

P0456 Evaporative emission system - very small leak detected

Possible causes: Mechanical fault, hose connection(s), EVAP pressure "sensor

P0457 Evaporative emission system - leak detected (fuel cap loose/off)

Possible causes: Mechanical fault, hose connection(s), EVAP pressure sensor

P0458 Evaporative emission system, purge control valve -circuit low

Possible causes: Wiring short to earth, EVAP valve

P0459 Evaporative emission system, purge control valve -circuit high
Possible causes: Wiring short to positive, EVAP valve

Evaporative Emission Purge Solenoid

Description & Operation
The duty cycle EVAP canister purge solenoid (DCP) regulates the rate of vapor flow from the EVAP canister to the intake manifold. The Powertrain Control Module (PCM) operates the solenoid.
During the cold start warm-up period and the hot start time delay, the PCM does not energize the solenoid. When de-energized, no vapors are purged. The PCM de-energizes the solenoid during open loop operation.
The engine enters closed loop operation after it reaches a specified temperature and the time delay ends. During closed loop operation, the PCM cycles (energizes and de-energizes) the solenoid 5 or 10 times per second, depending upon operating conditions. The PCM varies the vapor flow rate by changing solenoid pulse width. Pulse width is the amount of time that the solenoid is energized. The PCM adjusts solenoid pulse width based on engine operating condition.
Removal & Installation
The duty cycle evaporative (EVAP) canister purge solenoid is located in the engine compartment near the brake master cylinder.

1. Disconnect electrical connector at solenoid.
2. Disconnect vacuum lines at solenoid.
3. Lift solenoid slot from mounting bracket for Removal & Installation.

To Install:

1. Position solenoid slot to mounting bracket.
2. Connect vacuum lines to solenoid. Be sure vacuum lines are firmly connected and not leaking or damaged. If leaking, a Diagnostic Trouble Code (DTC) may be set with certain emission packages.
3. Connect electrical connector to solenoid.
   

Purge solenoid location:


EVAP cannister location:

That is a problem in the evaporative emission control system.
Could be anything causing it
Clogged filter in the charcoal canister
A leak in one of the vacuum lines
The purge valve not working,,,etc.
The best thing is to take it and have it checked out, they might have to do a smoke test to find the problem.
All they do is inject smoke into the system, if there is a leak the smoke will come out of it. All it takes is a pin hole in these emission systems to screw it all up.

P0446 Evaporative Emission System Vent Control Circuit.
The following are descriptions of all Evaporative possible codes:

P0441 Evaporative Emission System Incorrect Purge Flow
P0442 Evaporative Emission System Leak Detected (small leak)
P0443 Evaporative Emission System Purge Control Valve Circuit
P0444 Evaporative Emission System Purge Control Valve Circuit Open
P0445 Evaporative Emission System Purge Control Valve Circuit Shorted
P0446 Evaporative Emission System Vent Control Circuit
P0447 Evaporative Emission System Vent Control Circuit Open
P0448 Evaporative Emission System Vent Control Circuit Shorted
P0449 Evaporative Emission System Vent Valve/Solenoid Circuit
P0450 Evaporative Emission System Pressure Sensor/Switch
P0451 Evaporative Emission System Pressure Sensor/Switch Range/Performance
P0452 Evaporative Emission System Pressure Sensor/Switch Low
P0453 Evaporative Emission System Pressure Sensor/Switch High
P0454 Evaporative Emission System Pressure Sensor/Switch Intermittent
P0455 Evaporative Emission System Leak Detected (large leak)
P0456 Evaporative Emission System Leak Detected (very small leak)
P0457 Evaporative Emission System Leak Detected (fuel cap loose/off)
P0458 Evaporative Emission System Purge Control Valve Circuit Low
P0459 Evaporative Emission System Purge Control Valve Circuit High
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At least the cap isn't loose for the gas tank.

I would clear the code with an OBD-II Scanner 'erase code' button, and see how long it takes for it to come back.

check each wheel and make sure that the toothed ring on the wheel bearing hubs are tight and not spinning on the shaft