P0012 on Infiniti: How to Diagnose & Fix
Intake Camshaft Position Timing - Over-Retarded (Bank 1)
1 Infiniti model · 1 documented issue · 1 critical · $1,500-$3,500 repair
P0012 on Infiniti by model: symptoms, diagnosis and fix
The Q50's 2.0t uses the Mercedes-Benz M274 turbocharged four, shared with the C300 and GLC300. The timing chain and the camshaft adjusters (variable valve timing phasers) wear faster than the engine's design life, with problems commonly surfacing somewhere around 80,000 miles and reported as early as 60,000 on neglected cars. The first symptom is a brief metallic rattle on cold start as oil pressure builds and the tensioner takes up slack. Left alone, chain stretch throws off cam timing, sets correlation codes, and in the worst cases the chain skips teeth or breaks, which on this interference engine destroys valves and pistons. Extended oil change intervals and low oil level accelerate the wear.
Common Symptoms
- Metallic rattle for one to three seconds on cold start
- Rattle or whine from the front of the engine that changes with RPM
- Check engine light with camshaft/crankshaft correlation codes
- Rough idle or reduced power
- Engine misfire or failure to start after a loud bang
How to Fix
Treat a cold-start rattle on the 2.0t as a timing issue until proven otherwise rather than dismissing it as normal direct-injection noise. Have the shop scan for camshaft/crankshaft correlation codes and check actual cam timing against spec. Caught early, replacing the chain, tensioner, guides, and both camshaft adjusters is far cheaper than the engine. Change oil every 5,000 miles with the correct low-ash full synthetic instead of following the extended factory interval, and check the level between changes — this engine also consumes oil, and running it low is what kills the chain. On a used purchase, cold-start the car yourself before buying; a seller who has the engine already warm may be hiding exactly this noise.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- Genuine Infiniti M274 primary timing chainOEM13028-HG00F
Measured chain-wear/stretch branch Fitment/availability: 13028-HG00F supersedes 13028-HG00C and 13028-90C0N and fits listed Q50 2LTURBO applications. Confirm 2016-2018 U.S.
- Genuine Infiniti M274 chain tensioner/adjuster assemblyOEM13070-HG00F
Confirmed primary chain-tensioner/adjuster failure branch Fitment/availability: 13070-HG00F fits listed Q50 2LTURBO applications and is cataloged as the chain tensioner/tensioner adjuster. Confirm VIN and test result; do not confuse it w…
- Genuine Infiniti M274 slack-side timing-chain guideOEM13091-HG00B
Worn or damaged slack-side guide branch during confirmed timing service Fitment/availability: 13091-HG00B fits listed Q50 2LTURBO applications and is the slack-side/at-cylinder-head guide. Confirm VIN and diagram position; it is not the …
- Genuine Infiniti M274 tension-side timing-chain guideOEM13085-HG00B
Worn or damaged lower tension-side guide branch during confirmed timing service Fitment/availability: 13085-HG00B fits listed Q50 2LTURBO applications and is the lower tension-side guide. Confirm VIN and diagram position; the catalog als…
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Sources for this issue (3)
P0012 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 P0012 mean on a Infiniti?
P0012 stands for "Intake Camshaft Position Timing - Over-Retarded (Bank 1)." This code means the intake camshaft timing on Bank 1 is more retarded than the computer commanded — the variable valve timing system isn't reaching its target position. The computer controls camshaft timing through an oil-fed actuator (cam phaser) and a control solenoid; when actual timing lags the desired setting, this code sets. It is commonly caused by oil flow problems (low, dirty, or wrong oil), a stuck solenoid, or a worn cam phaser. Symptoms can include rough idle, reduced power, poor fuel economy, and sometimes rattling on startup. On Infiniti it is documented across 1 model: Q50.
What are the most common causes of P0012?
The most common causes of P0012 are: Low, dirty, or incorrect-viscosity engine oil, Faulty or stuck intake camshaft (VVT) oil control solenoid, Worn or stuck camshaft phaser/actuator, Clogged solenoid screen or oil passages, Wiring or connector problems at the solenoid, Timing chain wear or stretch affecting cam timing, Faulty camshaft position sensor. The specific cause varies by vehicle.
How much does it cost to fix P0012 on a Infiniti?
Published repair estimates on Infiniti range from $1,500 to $3,500 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 P0012 on a different make?
View P0012 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.