P0021 on Mercedes-Benz
Intake Camshaft Position Timing - Over-Advanced (Bank 2)
P0021 on Mercedes-Benz vehicles indicates intake camshaft position timing - over-advanced (bank 2). Au7o has documented this code across 1 Mercedes-Benz model — most commonly on GLE. P0021 means the engine computer detected that the intake camshaft on bank 2 is timed too far advanced and won't return to its commanded position. Most modern engines use variable valve timing (VVT), where an oil-pressure-driven actuator rotates the camshaft to optimize power and efficiency; the PCM compares the camshaft's actual position to its target. When the cam stays over-advanced beyond an acceptable limit, this code sets. Bank 2 refers to the side of the engine that does not contain cylinder number one. You may notice rough idle, reduced performance, or lower fuel economy. Typical repair costs on Mercedes-Benz range from $700 to $2,500, depending on the specific model and root cause.
Common Causes of P0021
- •Dirty or low engine oil restricting the VVT system
- •Stuck or failed camshaft oil control valve (VVT solenoid) on bank 2
- •Clogged VVT solenoid screen or oil passage
- •Faulty camshaft position actuator / phaser
- •Wiring or connector fault at the VVT solenoid
- •Camshaft or crankshaft position sensor problems
- •Worn timing chain, guides, or stretched chain altering cam timing
P0021 on Mercedes-Benz by Model
Mercedes-Benz GLE(1 issue)
- M276 V6 Camshaft Adjuster (Magnet/Solenoid) Wear and Cold-Start Rattle2016-2018
The W166 GLE 350 and GLE 400 (2016-2018, M276 3.0L/3.5L V6) share the well-known M276 camshaft-adjuster problem. The variable-valve-timing camshaft adjusters and their magnets/solenoids wear, allowing the cams to fall out of time. Symptoms include a 2-3 second rattle on cold start, rough running, and check-engine codes such as P0010-style adjuster faults; owners report codes like P002177 with cams found advanced/out of time. Left unaddressed, a worn adjuster can cause poor timing control and driveability problems.
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View P0021 across all makes →Frequently Asked Questions
What does P0021 mean on Mercedes-Benz?▼
P0021 stands for "Intake Camshaft Position Timing - Over-Advanced (Bank 2)." P0021 means the engine computer detected that the intake camshaft on bank 2 is timed too far advanced and won't return to its commanded position. Most modern engines use variable valve timing (VVT), where an oil-pressure-driven actuator rotates the camshaft to optimize power and efficiency; the PCM compares the camshaft's actual position to its target. When the cam stays over-advanced beyond an acceptable limit, this code sets. Bank 2 refers to the side of the engine that does not contain cylinder number one. You may notice rough idle, reduced performance, or lower fuel economy. On Mercedes-Benz specifically, this code is documented across 1 model.
What causes P0021 on Mercedes-Benz vehicles?▼
Common causes on Mercedes-Benz: Dirty or low engine oil restricting the VVT system, Stuck or failed camshaft oil control valve (VVT solenoid) on bank 2, Clogged VVT solenoid screen or oil passage, Faulty camshaft position actuator / phaser, Wiring or connector fault at the VVT solenoid. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0021 on a Mercedes-Benz?▼
Repair costs on Mercedes-Benz range from $700 to $2,500, depending on the specific model and root cause.
Which Mercedes-Benz models have P0021 documented?▼
Au7o has documented P0021 on 1 Mercedes-Benz model: GLE.