P03AF on Volkswagen
Cylinder 3 Pressure Too High
P03AF on Volkswagen vehicles indicates cylinder 3 pressure too high. Au7o has documented this code across 1 Volkswagen model — most commonly on Golf R. P03AF indicates the engine control module (ECM) has detected that the in-cylinder combustion pressure in cylinder 3 is higher than the expected/plausible range. It is set on engines equipped with in-cylinder pressure sensors (commonly VW/Audi diesel and some direct-injection applications) and typically triggers the EPC/check-engine light; the ECM may deactivate or de-rate the affected cylinder. The fault can be caused by an actual combustion/fueling problem or by a faulty pressure sensor sending an implausible signal. Typical repair costs on Volkswagen range from $1,500 to $4,200, depending on the specific model and root cause.
Common Causes of P03AF
- •Faulty or leaking fuel injector on cylinder 3 delivering excess fuel
- •Defective or out-of-calibration in-cylinder pressure sensor (implausible signal)
- •Wiring, connector, or harness fault to the cylinder 3 pressure sensor
- •Mechanical engine fault (head gasket leak, carbon buildup, bent valve, or compression abnormality)
- •ECM software/calibration error falsely recording high cylinder pressure (known VW/Audi issue, fixed by software update)
- •Worn or faulty spark/glow plug affecting combustion in cylinder 3
P03AF on Volkswagen by Model
Volkswagen Golf R(1 issue)
- EA888 Timing Chain Stretch and Tensioner Failure2014-2019
The 2.0 TSI EA888 Gen 3 (CJXC/DJHA engine codes) in the Mk7/Mk7.5 Golf R is prone to timing chain stretch and timing chain tensioner degradation, typically surfacing around 100,000-140,000 km. The plastic-bodied tensioner loses hydraulic tension and the chain develops slack, allowing the chain to skip teeth. In severe cases the timing jumps (owners report a slip of ~1.5 teeth), throwing a crankshaft/camshaft correlation fault and, if it lets go at speed, causing piston-to-valve contact and major internal damage. This is the same chain-drive architecture covered by an Audi TPI for 2015 cars. Symptoms most often start as a metallic rattle on cold start or a sudden loud rattle while driving.
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View P03AF across all makes →Frequently Asked Questions
What does P03AF mean on Volkswagen?▼
P03AF stands for "Cylinder 3 Pressure Too High." P03AF indicates the engine control module (ECM) has detected that the in-cylinder combustion pressure in cylinder 3 is higher than the expected/plausible range. It is set on engines equipped with in-cylinder pressure sensors (commonly VW/Audi diesel and some direct-injection applications) and typically triggers the EPC/check-engine light; the ECM may deactivate or de-rate the affected cylinder. The fault can be caused by an actual combustion/fueling problem or by a faulty pressure sensor sending an implausible signal. On Volkswagen specifically, this code is documented across 1 model.
What causes P03AF on Volkswagen vehicles?▼
Common causes on Volkswagen: Faulty or leaking fuel injector on cylinder 3 delivering excess fuel, Defective or out-of-calibration in-cylinder pressure sensor (implausible signal), Wiring, connector, or harness fault to the cylinder 3 pressure sensor, Mechanical engine fault (head gasket leak, carbon buildup, bent valve, or compression abnormality), ECM software/calibration error falsely recording high cylinder pressure (known VW/Audi issue, fixed by software update). Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P03AF on a Volkswagen?▼
Repair costs on Volkswagen range from $1,500 to $4,200, depending on the specific model and root cause.
Which Volkswagen models have P03AF documented?▼
Au7o has documented P03AF on 1 Volkswagen model: Golf R.