P052E on Subaru
Positive Crankcase Ventilation Regulator Valve Performance
P052E on Subaru vehicles indicates positive crankcase ventilation regulator valve performance. Au7o has documented this code across 2 Subaru models — most commonly on Ascent, WRX. P052E indicates a performance problem with the positive crankcase ventilation (PCV) regulator valve, the valve that meters blow-by gases from the engine crankcase back into the intake to be burned. The computer monitors crankcase pressure or related readings, and when the PCV regulator isn't controlling flow within the expected range, it sets this code. Symptoms can include rough idle, oil leaks from seals due to pressure imbalance, whistling/sucking noises, or increased oil consumption. It points to the PCV valve or ventilation system rather than the fuel or ignition system.
Common Causes of P052E
- •Stuck, clogged, or failed PCV regulator valve
- •Cracked or disconnected PCV hose/line
- •Vacuum leak in the crankcase ventilation system
- •Clogged PCV passages from sludge or carbon
- •Faulty crankcase pressure sensor
- •Damaged valve cover with integrated PCV (where applicable)
- •Wiring or connector fault on electrically controlled PCV valves
P052E on Subaru by Model
Subaru Ascent(1 issue)
- FA24F PCV Hose Oil/Fuel/Hot-Rubber Odor Under Hood (TSB 11-204-23)2019-2022
Owners report a strong oil, gasoline or hot-rubber smell from the engine bay, sometimes accompanied by oil seepage at the PCV hose joint. Subaru traced this to an undersized PCV hose clamp on the FA24F that allows blow-by vapors and oil mist to escape. TSB 11-204-23 prescribes a revised PCV hose assembly and improved spring clamp.
Subaru WRX(1 issue)
- Excessive Oil Consumption2015-2021
The FA20DIT engine can consume oil at a rate higher than expected, sometimes up to 1 quart every 1,000-3,000 miles. This is often related to the turbocharger, PCV system, or piston ring design. Subaru considers up to 1 quart per 1,200 miles as within normal range.
Looking for P052E on a different make?
View P052E across all makes →Frequently Asked Questions
What does P052E mean on Subaru?▼
P052E stands for "Positive Crankcase Ventilation Regulator Valve Performance." P052E indicates a performance problem with the positive crankcase ventilation (PCV) regulator valve, the valve that meters blow-by gases from the engine crankcase back into the intake to be burned. The computer monitors crankcase pressure or related readings, and when the PCV regulator isn't controlling flow within the expected range, it sets this code. Symptoms can include rough idle, oil leaks from seals due to pressure imbalance, whistling/sucking noises, or increased oil consumption. It points to the PCV valve or ventilation system rather than the fuel or ignition system. On Subaru specifically, this code is documented across 2 models.
What causes P052E on Subaru vehicles?▼
Common causes on Subaru: Stuck, clogged, or failed PCV regulator valve, Cracked or disconnected PCV hose/line, Vacuum leak in the crankcase ventilation system, Clogged PCV passages from sludge or carbon, Faulty crankcase pressure sensor. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P052E on a Subaru?▼
Repair costs vary widely depending on the root cause and specific Subaru model.
Which Subaru models have P052E documented?▼
Au7o has documented P052E on 2 Subaru models: Ascent, WRX.