P0018 on BMW: How to Diagnose & Fix
Crankshaft/Camshaft Position Correlation - Bank 2 Sensor A
4 BMW models · 4 documented issues · 4 critical · $2,500-$14,000 repair
P0018 on BMW by model: symptoms, diagnosis and fix
BMW SIB 11 16 14 includes F12 6 Series convertibles with the N63 engine produced from March 2011 through July 2012 and F13 6 Series coupes with the N63 engine produced from July 2011 through July 2012. It defines an ISTA timing-chain elongation test; BMW states that the check and related Customer Care Package are not recalls or mandatory technical campaigns.
Common Symptoms
- Stored VANOS or camshaft-position faults require diagnosis before the chain test
- BMW timing-chain elongation test reports not OK
How to Fix
Confirm the N63 engine, chassis, production date and VIN history, resolve stored VANOS or camshaft-position faults first, and have a BMW-qualified technician run the prescribed timing-chain test. Replace both chains only if the approved test reports that the chain is not OK. ShowMeTheParts resolved the exact 2012 650i ENGINE COMPONENTS fitment but returned no timing-chain candidate, so no commerce link is approved.
Sources for this issue (1)
The N20 2.0L turbocharged engine in 2015-2016 X4 xDrive28i models suffers from premature timing chain stretch and guide failure, typically between 40,000-80,000 miles. The single-row timing chain design is inadequate for the engine's power output. Chain stretch causes timing to jump, leading to rough running, poor performance, and potential catastrophic engine damage if the chain breaks. BMW issued a class action settlement covering 8 years/100,000 miles. This is identical to the N20 issue affecting all N20-powered BMW models including X3, 3/4 Series, and X1.
Common Symptoms
- Rattling noise from engine on cold start (first 5 seconds)
- Check engine light with timing correlation codes (P0016, P0017, P0018, P0019)
- Rough idle or misfires
- Loss of power or hesitation on acceleration
- Engine won't start after chain failure
How to Fix
Complete timing chain kit replacement including chain, guides, tensioner, and sprockets. Must be performed by experienced BMW technician. Preventive replacement recommended at 60,000-80,000 miles. BMW extended warranty to 8 years/100,000 miles under class action settlement. Upgraded reinforced chain kit available from aftermarket. Labor is 10-14 hours for X4 due to AWD and tight engine bay.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- FCP Euro BMW N20/N26 xDrive complete timing-chain kit 11318648732KT2OEM11318648732Cross-ref11318648732KT2
Complete timing-system parts package after confirmed N20 timing-chain/guide failure or an approved preventive repair. Confirm VIN, production date, kit contents, one-time-use hardware, fluids and special-tool requirements before ordering…
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 (1)
The N20 2.0L turbocharged engine in 428i models suffers from premature timing chain stretch and guide failure, typically occurring between 40,000-80,000 miles. The single-row timing chain design is inadequate for the engine's power output. Chain stretch causes the timing to jump, leading to rough running, poor performance, and potential catastrophic engine damage if the chain breaks. BMW issued a class action settlement covering 8 years/100,000 miles. This is identical to the N20 timing chain issue in 328i/X3/X5 models using the same engine.
Common Symptoms
- Rattling noise from engine on cold start (first 5 seconds)
- Check engine light with timing correlation codes (P0016, P0017, P0018, P0019)
- Rough idle or misfires
- Loss of power or hesitation on acceleration
- Engine won't start after chain failure
How to Fix
Complete timing chain kit replacement including chain, guides, tensioner, and sprockets. Must be performed by experienced BMW technician. Preventive replacement recommended at 60,000-80,000 miles. BMW extended warranty to 8 years/100,000 miles under class action settlement. Upgraded reinforced chain kit available from aftermarket.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- Iwis N20 timing-chain kit 11315A19AA2
Fitment: F32/F33/F36 BMW 428i and 428i xDrive with N20 as listed by Turner; use the vehicle selector and confirm VIN/production date. Kit lists chain, gaskets, guides/rails, sprocket and hardware; technician must confirm any additional o…
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 (1)
The N63 twin-turbo V8 places the turbos inside the vee, and the trapped heat cooks the plastic timing chain guides until they crack and break apart. Debris from a shattered guide lets the chain go slack, so it stretches, throws timing correlation codes, and can jump a tooth - at which point one whole bank stops firing and the driver gets a Drive Train Malfunction with reduced power. Owners on the F01 chassis have reported broken guides and a jumped chain around 100,000-120,000 miles, often preceded for months by a rattle or grinding noise during the first few seconds after a cold start. Early N63 engines (roughly 2009-2013) were the worst and were covered in part by the Customer Care Package rework.
Common Symptoms
- Rattle or grinding for a few seconds at cold start
- Drive Train Malfunction warning
- One bank of cylinders stops firing
- Rough running and severe loss of power
- Check engine light with timing correlation codes
How to Fix
Do not ignore a cold-start rattle on an N63. Pull the DME for timing correlation codes and check the chain wear with a scope before it jumps. The repair replaces the complete kit - chains, guides, tensioners and sprockets on both banks - because reusing any one worn part causes a repeat failure. The engine has to come out and be largely disassembled; it is roughly a 40-hour job, which is why quotes land in the five-figure range at a dealer. If the chain has already jumped, the valves may be bent and the heads need inspection.
Sources for this issue (3)
P0018 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 P0018 mean on a BMW?
P0018 stands for "Crankshaft/Camshaft Position Correlation - Bank 2 Sensor A." This code means the computer detected that the crankshaft and the Bank 2 'A' (typically intake) camshaft are out of their expected timing relationship. The computer compares the crankshaft and camshaft position sensor signals; they should stay in a fixed correlation as the engine turns. When the Bank 2 camshaft is too far off from the crankshaft, P0018 sets, indicating the valve timing on that bank is misaligned. This can cause rough running, reduced power, hard starting, or a no-start, and in some cases signals timing chain or phaser trouble that warrants prompt attention. On BMW it is documented across 4 models: 6 Series, X4, 4 Series, 7 Series.
What are the most common causes of P0018?
The most common causes of P0018 are: Stretched, worn, or jumped timing chain (Bank 2), Worn or broken timing chain guides/tensioner, Stuck variable valve timing solenoid or phaser, Low or dirty engine oil affecting the phaser, Faulty crankshaft or camshaft position sensor, Damaged reluctor/tone ring, Incorrect timing from prior service, Wiring or connector fault at a cam/crank sensor. The specific cause varies by vehicle.
How much does it cost to fix P0018 on a BMW?
Published repair estimates on BMW range from $2,500 to $14,000 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 P0018 on a different make?
View P0018 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.