Diagnostic Trouble Code
P052E
Positive Crankcase Ventilation Regulator Valve Performance
Technical Description P052E
Positive Crankcase Ventilation Regulator Valve Performance
Severity Level P052E
Incorrect crankcase pressure may result in engine oil leaks. A code P052E should be categorized as severe and addressed accordingly.
What Does This Mean P052E?
This generic powertrain diagnostic trouble code (DTC) typically applies to many OBD-II vehicles. That may include but is not limited to vehicles from Ford, Dodge, Ram, Volvo, etc.
If you have a code P052E stored in your OBD-II vehicle, it means that the powertrain control module (PCM) has detected a signal from the crankcase pressure sensor that indicates an inappropriate degree of pressure exists.
Air density (pressure) in the engine crankcase is monitored by the PCM using an input voltage signal from the crankcase pressure sensor. Crankcase pressure sensor input voltage is received (by the PCM) as actual units of pressure. Either kilopascal (kPa) units or inches of mercury (Hg) are used to measure crankcase pressure. The crankcase pressure sensor is typically located in or near one of the valve covers.
Because the lower end of the internal combustion engine must be sealed to prevent oil leaks, a certain amount of pressure is created there. This pressure is caused by drastic changes in temperature, the vapors created by engine oil, and the rapid centrifugal motion of the crankshaft, connecting rods, etc.
The positive crankcase ventilation (PCV) system uses carefully controlled intake vacuum to draw pressure from the crankcase through a specially designed valve (PCV valve) that only allows a single direction of flow. In the vast majority of vehicle applications, the PCV valve uses straight vacuum from the intake manifold. In this particular application, PCV vacuum is regulated using an electronically controlled PCV regulator valve. The PCM uses an input signal from the crankcase pressure sensor to determine how much vacuum pressure must be applied to the PCV for optimum performance. A constant supply of battery voltage is usually applied to one terminal of the PCV regulator valve and the PCM supplies a ground as needed to complete the circuit, position the regulator valve in its housing, and realize the desired degree of PCV vacuum.
If the PCM detects that the desired level of crankcase pressure cannot be achieved with the PCV regulator valve, a code P052E will be stored and a malfunction indicator lamp (MIL) may be illuminated.
If you have a code P052E stored in your OBD-II vehicle, it means that the powertrain control module (PCM) has detected a signal from the crankcase pressure sensor that indicates an inappropriate degree of pressure exists.
Air density (pressure) in the engine crankcase is monitored by the PCM using an input voltage signal from the crankcase pressure sensor. Crankcase pressure sensor input voltage is received (by the PCM) as actual units of pressure. Either kilopascal (kPa) units or inches of mercury (Hg) are used to measure crankcase pressure. The crankcase pressure sensor is typically located in or near one of the valve covers.
Because the lower end of the internal combustion engine must be sealed to prevent oil leaks, a certain amount of pressure is created there. This pressure is caused by drastic changes in temperature, the vapors created by engine oil, and the rapid centrifugal motion of the crankshaft, connecting rods, etc.
The positive crankcase ventilation (PCV) system uses carefully controlled intake vacuum to draw pressure from the crankcase through a specially designed valve (PCV valve) that only allows a single direction of flow. In the vast majority of vehicle applications, the PCV valve uses straight vacuum from the intake manifold. In this particular application, PCV vacuum is regulated using an electronically controlled PCV regulator valve. The PCM uses an input signal from the crankcase pressure sensor to determine how much vacuum pressure must be applied to the PCV for optimum performance. A constant supply of battery voltage is usually applied to one terminal of the PCV regulator valve and the PCM supplies a ground as needed to complete the circuit, position the regulator valve in its housing, and realize the desired degree of PCV vacuum.
If the PCM detects that the desired level of crankcase pressure cannot be achieved with the PCV regulator valve, a code P052E will be stored and a malfunction indicator lamp (MIL) may be illuminated.
Symptoms P052E
1
Engine oil leaks
2
Smoke (steam) from underhood area
3
Hissing (sucking) noise from engine area
4
Drivability issues created by a vacuum leak
Possible Causes P052E
1
Bad PCV regulator valve
2
Faulty PCV valve
3
Defective crankcase pressure sensor
4
Open or shorted PCV regulator valve/crankcase pressure sensor wiring
5
PCM malfunction or PCM programming error
Solutions & Repair Steps P052E
In my experience, a manual vacuum pressure gauge, a diagnostic scanner, a digital volt/ohmmeter (DVOM), and a reliable source of vehicle information will be necessary when diagnosing a code P052E.
A manual vacuum pressure test should be performed prior to diagnosing any insufficient crankcase pressure/PCV related codes. If the engine fails to produce enough vacuum, it must be repaired before moving forward with your diagnosis. To conduct a manual vacuum pressure test, disconnect the PCV vacuum hose and attach your vacuum pressure gauge to it. Your vehicle information resource should yield specifications regarding minimum engine vacuum.
Check all PCV hoses for signs of cracking or breakage and make repairs as necessary. Cracked or collapsed PCV vacuum hoses may contribute to the conditions which caused the P052E to be stored.
If the engine is in good working order and there are no vacuum leaks, continue with a visual inspection of all PCV regulator valve and crankcase pressure sensor wiring and connectors. Make repairs as needed. Next, I would connect the scanner to the vehicle diagnostic port and retrieve all stored codes and freeze frame data. Writing this information down may aid you as your diagnosis unfolds. After that, clear the codes and test-drive the vehicle to see if the code is reset.
Utilize your vehicle information resource to obtain connector face views, wiring diagrams, connector pin-out charts, component testing procedures and specifications. All this information will be required to proceed with your diagnosis.
Test PCV regulator valve and circuits (KOEO)
Test for a PCV regulator valve voltage output circuit at the PCM connector
Test the crankshaft pressure sensor using the DVOM
Use the DVOM to test for reference voltage (typically 5-volts) and a ground at the crankcase pressure sensor connector
Test crankcase pressure sensor signal circuit voltage using the DVOM
Test the crankcase pressure sensor signal circuit at the PCM connector
If the PCV regulator valve/crankcase pressure sensor and all circuits are within specifications, suspect PCM failure or a PCM programing error.
A manual vacuum pressure test should be performed prior to diagnosing any insufficient crankcase pressure/PCV related codes. If the engine fails to produce enough vacuum, it must be repaired before moving forward with your diagnosis. To conduct a manual vacuum pressure test, disconnect the PCV vacuum hose and attach your vacuum pressure gauge to it. Your vehicle information resource should yield specifications regarding minimum engine vacuum.
Check all PCV hoses for signs of cracking or breakage and make repairs as necessary. Cracked or collapsed PCV vacuum hoses may contribute to the conditions which caused the P052E to be stored.
If the engine is in good working order and there are no vacuum leaks, continue with a visual inspection of all PCV regulator valve and crankcase pressure sensor wiring and connectors. Make repairs as needed. Next, I would connect the scanner to the vehicle diagnostic port and retrieve all stored codes and freeze frame data. Writing this information down may aid you as your diagnosis unfolds. After that, clear the codes and test-drive the vehicle to see if the code is reset.
Utilize your vehicle information resource to obtain connector face views, wiring diagrams, connector pin-out charts, component testing procedures and specifications. All this information will be required to proceed with your diagnosis.
Test PCV regulator valve and circuits (KOEO)
Test for a PCV regulator valve voltage output circuit at the PCM connector
Test the crankshaft pressure sensor using the DVOM
Use the DVOM to test for reference voltage (typically 5-volts) and a ground at the crankcase pressure sensor connector
Test crankcase pressure sensor signal circuit voltage using the DVOM
Test the crankcase pressure sensor signal circuit at the PCM connector
If the PCV regulator valve/crankcase pressure sensor and all circuits are within specifications, suspect PCM failure or a PCM programing error.