After a h/c work, I am getting this code. I did a search and came up with DTC P0443 Evaporative Emission (EVAP) Purge Solenoid Control Circuit. Is this a concern? I remember removing the AIR and did not see a vacuum line to the pump and I read somewhere that you have to block it. Thanks.

 

I'd check all the connections and wiring for this system first.

Circuit Description
The PCM controls the EVAP canister purge valve by grounding the control circuit via an internal switch called a driver. The primary function of the driver is to supply the ground for the controlled component. Each driver has a fault line which the PCM monitors. When the PCM commands a component ON, the voltage of the control circuit should be low (near 0 volts). When the PCM commands the control circuit to a component OFF, the voltage potential of the circuit should be high (near the battery voltage). If the fault detection circuit senses a voltage other than what the PCM expects, the fault line status changes causing the DTC to set. The EVAP Purge Solenoid Valve is pulse width modulated (PWM). The PCM controls the EVAP canister purge solenoid valve duty cycle by controlling the amount of purge solenoid valve ON time. The scan tool displays the amount of ON time in a percentage. This value is the amount of available vacuum that will be applied to the EVAP system.

Conditions for Running the DTC


The engine speed is greater than 400 RPM.
The system voltage is between 6 volts and 18 volts.
Conditions for Setting the DTC


The PCM detects that the commanded state of the driver and the actual state of the control circuit do not match.
All the above conditions present for a minimum of 5.0 seconds.
Action Taken When the DTC Sets


The PCM illuminates the Malfunction Indicator Lamp on the second consecutive ignition cycle that the diagnostic runs and fails.
The PCM records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the PCM stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the PCM records the operating conditions at the time of the failure. The PCM writes the conditions to the Freeze Frame and updates the Failure records.
Conditions for Clearing the MIL/DTC


The PCM turns the MIL OFF after three consecutive ignition cycles that the diagnostic runs and does not fail.
A last test failed (current DTC) clears when the diagnostic runs and does not fail.
A History DTC clears after forty consecutive warm-up cycles, if this or any other emission related diagnostic does not report any failures.
Use a scan tool in order to clear the MIL/DTC.
Diagnostic Aids

Important :


Remove any debris from the PCM/TAC module connector surfaces before servicing the PCM/TAC module. Inspect the PCM/TAC module connector gaskets when diagnosing/replacing the modules. Ensure that the gaskets are installed correctly. The gaskets prevent contaminant intrusion into the PCM/TAC modules.
For any test that requires probing the PCM or a component harness connector, use the Connector Test Adapter kit J 35616-A. Using this kit prevents damage to the harness/component terminals.
The following may cause an intermittent:
Poor connections
Corrosion
Mis-routed harness
Rubbed through wire insulation
Broken wire inside the insulation
Using Freeze Frame and/or Failure Records data may aid in locating an intermittent condition. If you cannot duplicate the DTC, the information included in the Freeze Frame and/or Failure Records data can aid in determining how many miles since the DTC set. The Fail Counter and Pass Counter can also aid determining how many ignition cycles the diagnostic reported a pass and/or a fail. Operate the vehicle within the same freeze frame conditions (RPM, load, vehicle speed, temperature etc.) that you observed. This will isolate when the DTC failed.
For an intermittent, refer to Symptoms. See: Diagnosis By Symptom - Computers and Control Systems
Test Description
The numbers below refer to the step numbers on the diagnostic table.


Listen for an audible click when the solenoid operates. Be sure that both the ON and the OFF states are commanded. Repeat the commands as necessary. The Fuel Tank Pressure sensor parameter on the scan tool can also be used to determine if the EVAP purge solenoid is operating. You should be able to see the pressure/vacuum change when you command the solenoid on.
This test can detect a partially shorted coil which would cause excessive current flow. Leaving the circuit energized for 2 minutes allows the coil to warm up. When warm, the coil may open (amps drop to 0), or short (goes above 0.75 amp).
Listen for an audible click when the solenoid operates. Repeat the procedure as necessary.
If no trouble is found in the control circuit or the connection at the PCM, the PCM may be faulty, however, this is an extremely unlikely failure.

 

When the intake is removed, the only two parts of the EVAP system removed are the solenoid electrical connector (driver's side between the intake and valve cover at center of motor) and the EVAP hose between the solenoid and the hose at the firewall. Check these first, the hose or connector may not be on fully.