P0014 on Mercedes-Benz: How to Diagnose & Fix
Exhaust Camshaft Position Timing - Over-Advanced (Bank 1)
3 Mercedes-Benz models · 3 documented issues · 1 critical · $120-$5,000 repair
P0014 on Mercedes-Benz by model: symptoms, diagnosis and fix
The R231 SL with M276 V6 or M278 V8 engines develops a distinctive rattling noise from the timing chain area on cold starts. The cam adjuster magnets (variators) lose oil pressure overnight, allowing the chains to slap against the guides until oil pressure builds. This noise worsens over time and can eventually lead to stretched chains and timing issues.
Common Symptoms
- Rattling noise on cold start lasting 2-5 seconds
- Check engine light with camshaft timing codes
- Noise worsening over time
- Slight rough idle when cold
How to Fix
Replace the timing chain tensioners and cam adjuster magnets (variators). Updated parts are available that improve oil retention. In advanced cases, the timing chains and guides should also be replaced. Use only Mercedes-approved 0W-40 or 5W-30 oil to maintain proper cold-start viscosity.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- Genuine Mercedes small-bore cylinder-head oil check valve A2780504000OEMMercedes-Benz A2780504000
Use only within the engine cutoff after bore measurement; two of
- Genuine Mercedes staged-8mm-bore cylinder-head oil check valve A2780503300OEMMercedes-Benz A2780503300
Use only within the engine cutoff after bore measur
- Febi M276 early left secondary-chain tensioner A2760502300OEMFebi / Mercedes A2760502300
Left tensioner through M276 engine 2769xx 30 129268 when LI05.10-P-056435 calls for tensioners Fitment/availability: The reviewed direct product/catalog destination identifies Febi 2760502300 for M276 applications. Use only with matching…
- Febi M276 early right secondary-chain tensioner A2760502400OEMFebi / Mercedes A2760502400
Right tensioner through M276 engine 2769xx 30 129268 when LI05.10-P-056435 calls for tensioners Fitment/availability: The inspected direct U.S. Use only with matching left 2760502300 through engine 129268 and only within
- Genuine Mercedes M276 later left secondary-chain tensioner A2760502500OEMMercedes-Benz A2760502500
Left tensioner from M276 engine 2769xx 30 129269 through the bulletin tensioner cutoff Fitment/availability: The inspected direct U.S. Use only with matching right 2760502600 from engine 129269 through 365996 when the
- Genuine Mercedes M276 later right secondary-chain tensioner A2760502600OEMMercedes-Benz A2760502600
Right tensioner from M276 engine 2769xx 30 129269 through the bulletin tensioner cutoff Fitment/availability: The inspected direct U.S. Use only with matching left 2760502500 from engine 129269 through 365996 when the
- Genuine Mercedes M278/M157 early left secondary-chain tensioner A2780501300OEMMercedes-Benz A2780501300
Early left tensioner for the bulletin branch through M278 engine 035185 or M157 engine 009366 Fitment/availability: The inspected direct U.S. Use only with matching right 2780501400 through the applicable engine
- Genuine Mercedes M278/M157 early right secondary-chain tensioner A2780501400OEMMercedes-Benz A2780501400
Early right tensioner for the bulletin branch through M278 engine 035185 or M157 engine 009366 Fitment/availability: The inspected direct U.S. Use only with matching left 2780501300 through the applicable engine
- Genuine Mercedes current later left M278/M157 tensioner A2780504700OEMMercedes-Benz A2780504700; supersedes A2780501500
Current replacement for later left A2780501500 within the bulletin tensioner branch Fitment/availability: The inspected direct U.S. page identifies genuine 2780504700 and showed it in stock with price and purchase controls; catalog subst…
- Genuine Mercedes current later right M278/M157 tensioner A2780504800OEMMercedes-Benz A2780504800; supersedes A2780501600
Current replacement for later right A2780501600 within the bulletin tensioner branch Fitment/availability: The inspected direct U.S. page identifies genuine 2780504800 and showed it in stock with price and purchase controls; catalog subs…
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Owner tips & cautions
- TipShort oil change intervals (every 7,500 miles with full synthetic) help prevent this issue. The extended 15,000-mile intervals Mercedes recommends are too long for these engines.
The M271 four-cylinder's camshaft adjuster magnets (variable valve timing solenoids) commonly fail or become oil-fouled on R171 SLK200 Kompressor and R172 SLK250 models. A well-documented M271 defect is engine oil wicking up the solenoid connector into the wiring harness toward the ECU and O2 sensor. This is distinct from timing-chain/gear wear: the solenoid itself sticks or shorts, upsetting cam timing and triggering camshaft-position/correlation codes.
Common Symptoms
- Check-engine light for camshaft position/correlation
- Rough idle or hesitation
- Oil in the solenoid connector / harness
- Occasional hard start or reduced power
- Fault code moves when magnets are swapped
How to Fix
Replace the camshaft adjuster magnet solenoids and fit Mercedes' updated oil-stop connector/harness (Oelstoppkabel, e.g. A2711502733) that resists oil migration; clean oil from the connector and harness. Because the adjuster still tends to seep, periodic replacement (roughly every 30,000-40,000 miles) is common, and more frequent oil changes slow sludge buildup. A quick diagnostic is swapping intake/exhaust magnets to see if the fault code follows the part.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- Genuine Mercedes M271 Kompressor camshaft-adjuster magnet A2710510177OEMMercedes-Benz A2710510177
M271 Kompressor external adjuster-magnet branch after electrical/actuation testing identifies the failed magnet Fitment/availability: The inspected direct U.S. page identifies genuine 2710510177 and showed availability, price and purchas…
- Genuine Mercedes M271 oil-stop adapter harness A2711502733 / current -65OEMMercedes-Benz A2711502733 / A271150273365
Confirm engine/VIN and connector;
- Genuine Mercedes M271 EVO camshaft-control solenoid A2711560090OEMMercedes-Benz A2711560090
R172 SLK250 M271 EVO control-solenoid branch after the specific solenoid is electrically and functionally proven faulty Fitment/availability: The inspected direct U.S. page identifies genuine 2711560090, explicitly labels SLK250 fitment,…
As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.
Sources for this issue (3)
The turbo petrol M270 (and naturally-aspirated M270/M274 in B180/B200/B250) uses a two-stage timing chain whose plastic guide rails and hydraulic tensioner degrade prematurely. Owners report a loud metallic rattle for roughly 1-15 seconds on cold start that fades as oil pressure builds. Short-trip urban use accelerates the problem because the cold-start period (low oil pressure) makes up a large share of running time. Stretch typically appears from ~80,000 km (50,000 mi), with some city cars rattling from ~70,000 km. Left unaddressed, chain stretch alters valve timing, throws fault codes, and risks contact/wear on cam bearings and phasers.
Common Symptoms
- Metallic rattle on cold start lasting 1-15 seconds
- Rattle fades once engine warms
- Rough running or misfire
- Reduced power
- Check engine light
How to Fix
Diagnose with a cold-start listen and read live chain/cam-position data via XENTRY. If only the tensioner is at fault, replacing the hydraulic chain tensioner first is the cheaper initial fix; if the chain is stretched, replace the complete OEM timing kit (chain, both guide rails, tensioner, and cam phaser sprockets if worn) to avoid consequential damage. Use the correct MB-Approval 229.5/229.51 0W-40 or 5W-40 oil and shorten oil-change intervals on short-trip cars.
Sources for this issue (3)
P0014 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P0014 mean on a Mercedes-Benz?
P0014 stands for "Exhaust Camshaft Position Timing - Over-Advanced (Bank 1)." P0014 means the exhaust camshaft on bank 1 is timed too far advanced — the variable valve timing (VVT) system has moved the cam beyond the position the computer commanded, or it's stuck in an over-advanced position. The engine uses VVT to rotate the camshaft and optimize valve timing for power, economy, and emissions; the computer compares the commanded cam position to the actual reading from the cam sensor and flags this code when they don't agree. Common results are rough idle, reduced power, poor fuel economy, or a rattle at start-up. Oil flow and the VVT actuator are the usual suspects. On Mercedes-Benz it is documented across 3 models: SL-Class, SLK/SLC, B-Class.
What are the most common causes of P0014?
The most common causes of P0014 are: Low or dirty engine oil restricting VVT operation, Stuck or failed camshaft oil control valve (VVT solenoid), Clogged VVT solenoid screen or oil passages, Faulty camshaft phaser/actuator, Wiring or connector fault at the oil control valve, Stretched timing chain or jumped timing, Camshaft position sensor fault giving incorrect reading. The specific cause varies by vehicle.
How much does it cost to fix P0014 on a Mercedes-Benz?
Published repair estimates on Mercedes-Benz range from $120 to $5,000 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for P0014 on a different make?
View P0014 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.