P0012 on BMW: How to Diagnose & Fix
Intake Camshaft Position Timing - Over-Retarded (Bank 1)
4 BMW models · 4 documented issues · 2 critical · $100-$32,000 repair
P0012 on BMW by model: symptoms, diagnosis and fix
The 4.4L twin-turbo N63 V8 in the X6 xDrive50i is known for timing chains that stretch and wear early. Cars.com reported that BMW issued service bulletin 11 16 14 because N63 timing chains "have been found to stretch and wear out prematurely," which leads to premature valvetrain wear and reduced engine performance. The bulletin covers N63 versions of the X6, X5, 5, 6 and 7 Series, among others, including the ActiveHybrid X6. For the X6, it applies to E71 models built from July 2008 to June 2014. A stretched chain throws off valve timing, and owner guides note this can reduce torque and throttle response. BMW handles the issue through the N63 Customer Care Package (SI B00 13 14). As part of that package, a dealer uses BMW's diagnostic software to measure chain stretch. The car is then reprogrammed to a shorter oil-change interval of 10,000 miles or 12 months, which BMW says is needed to avoid future valvetrain wear. Later F16 X6 xDrive50i models (2015-2018) are not on the bulletin's list of affected build dates.
Common Symptoms
- Rattling noise from the engine on cold starts
- Stored camshaft-position or VANOS fault codes
- Check engine light
- Loss of power or hesitation
How to Fix
What to check first: if an E71 X6 xDrive50i (built 7/2008-6/2014) rattles on a cold start or has camshaft-position or VANOS fault codes, ask a BMW dealer to run the timing chain test from SI B11 16 14. The test uses BMW's diagnostic software and reports either "Timing chain is OK" or "Timing chain is not OK." The bulletin says to fix any stored VANOS or camshaft faults before the chain test, because a bad VANOS actuator or solenoid can skew the result. If the chains measure as stretched, BMW's procedure replaces both timing chains (repair instruction 11 31 052). Coverage: the chain check is part of BMW's N63 Customer Care Package (SI B00 13 14). BMW says it is not a recall or a mandatory campaign. Dealers schedule it based on parts availability and their workshop capacity. Cars.com reported that the repair is covered under the new-car limited warranty or the certified pre-owned warranty, and possibly under an extended warranty once the factory warranty has expired. To see whether your car was already done, look on the B-pillar for a Service Action label with code 728 punched out. A dealer can also check your VIN for campaign code 00 13 48 02 00. Ask the dealer whether your VIN is still eligible and whether the chain replacement would be covered. After the repair, the car is reprogrammed to change the oil every 10,000 miles or 12 months. Keep to that interval, because BMW gives the shorter interval as the way to avoid future valvetrain wear. BMW's bulletins do not give a repair cost, so get an itemized quote from the dealer or an N63 specialist.
Call to confirm they can assess your vehicle and perform the stated work. Search results do not confirm qualification, eligibility or coverage.
Sources for this issue (4)
The N55 3.0L turbocharged inline-6 engine in 435i models experiences VANOS (Variable Valve Timing) solenoid failures. These solenoids control oil flow to the VANOS system for variable valve timing. Internal wear causes them to stick or fail, leading to rough running, power loss, and check engine lights. The intake VANOS solenoid (cylinder head front) fails more frequently than the exhaust solenoid. Oil contamination and sludge accelerate failure. This is a common issue shared with N55-powered 335i, 535i, and X5 35i models.
Common Symptoms
- Rough idle or engine stumble
- Check engine light with VANOS codes (P0011, P0012, P0021, P0022)
- Loss of power or poor throttle response
- Increased fuel consumption
- Cold start rough running that improves when warm
How to Fix
Replace failed VANOS solenoid(s). Both intake and exhaust solenoids should be inspected. Clean VANOS system if contaminated with sludge. Use high-quality full synthetic oil (BMW LL-01 spec) and maintain 7,500-mile oil change intervals to prevent premature failure. Some shops recommend replacing both solenoids preventively.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- Genuine BMW N55 VANOS solenoid valve 11368605123OEM11368605123
BMW catalogs quantity two but replace only the diagnosed failed position unless the repair plan calls for both; confirm VIN..
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 (2)
The S85 V10 uses a high-pressure VANOS pump to supply the oil pressure that moves the variable valve timing units. The pump works at about 115 bar. The high-pressure VANOS oil lines can leak at the fittings where the rigid metal pipe ends join the flexible hose section. A leak loses oil and lowers the pressure available to the VANOS system, and a parts seller warns this can lead to very expensive engine damage. BMW issued a service bulletin (SIB 11 10 05) to replace the VANOS high-pressure line on M5s produced up to 11/22/05. Buyer guides report that a failed line can starve the pump of pressure, which can cause the pump to fail and send metal debris through the engine. How much the repair costs depends on whether that debris has contaminated the rest of the engine. Low VANOS system pressure is the telltale sign of a leaking line.
Common Symptoms
- Rough idling and unstable idle speed
- Reduced power output and poor acceleration
- Poor fuel economy
- Rattling or grinding noise from engine bay at startup
- Oil leaks visible near front of engine (VANOS area)
- Check engine light with VANOS-related fault codes
How to Fix
Check first: look for oil leaks around the VANOS lines at the front of the engine, and have a shop check VANOS system pressure. Low pressure points to a leaking line. On early cars (built up to 11/22/05), check the service records for the SIB 11 10 05 line replacement, and ask any seller for records of VANOS line inspection or replacement. Fix: replace the leaking line with the current genuine BMW part. 11 36 7 838 670 is the pressure hose that runs from the pressure accumulator to the VANOS units. 11 36 7 838 669 is the hose that runs from the high-pressure oil pump to the other pressure hose. When you replace a line, also replace the crush washers at each end (4 in total) and, on the 838 669 hose, the O-ring at the top. The banjo bolts are cheap and optional. Getting to the 838 669 hose means removing the oil pan, so it is often replaced at the same time as the rod bearings. If the pump has failed and shed metal debris, the rest of the engine needs to be checked for contamination. Fix a known VANOS line leak promptly rather than driving on it. A published buyer guide puts VANOS high-pressure pump failure at $3,000 to $32,000, depending on whether debris has contaminated the rest of the engine.
Call to confirm they can assess your vehicle and perform the stated work. Search results do not confirm qualification, eligibility or coverage.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- Genuine BMW S85 VANOS oil line 11367838669OEM11367838669
The retailer specifies four 07119963129 copper washers and one 11367834552 O-ring as additional required items; verify VIN and the exact failed line..
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 (5)
The VANOS (Variable Valve Timing) system on all E85 and E89 Z4 engines (M54, N52, N54, N20) suffers from solenoid failures, typically beyond 100,000 miles. The VANOS solenoids control oil flow to the variable camshaft timing adjustment units, and they fail through three primary modes: solenoid coil pack malfunction, sticking solenoid valves from oil varnish buildup, and deteriorating solenoid sealing plate rubber rings. When VANOS solenoids fail, the engine loses its ability to optimize valve timing, causing rough idle, power loss, poor fuel economy, and unusual engine noises. The good news: VANOS solenoids are inexpensive and relatively easy to replace - one of the simpler E85/E89 repairs.
Common Symptoms
- Rough or uneven idle with RPM fluctuations
- Noticeable loss of power during acceleration
- Engine misfires causing hesitation or jerking
- Check engine light with VANOS-related fault codes (2A82, 2A87, 2A9A, 2A9F)
How to Fix
Replace VANOS solenoids - inexpensive and straightforward repair. Replace all solenoids at once even if only one has failed - the others are same age and will fail soon. Also replace VANOS solenoid O-rings and sealing plates during service.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- Beisan BS001 double-VANOS seals repair kit
M54 internal double-VANOS seal repair after confirmed seal degradation. Confirm engine and internal VANOS diagnosis before ordering..
- Genuine BMW N52/N54 VANOS solenoid valve 11367585425OEM11367585425
Confirmed N52/N54 intake or exhaust VANOS solenoid replacement. Replace only the failed/test-confirmed unit or both when the repair decision specifically calls for it.
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)
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 BMW?
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 BMW it is documented across 4 models: X6, 4 Series, M5, Z4.
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 BMW?
Published repair estimates on BMW range from $100 to $32,000 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 P0012 on a different make?
View P0012 across all makes →Join 700+ subscribers following Au7o for vehicle insights and updates.
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.