If your OBD-II scanner displays P0018, your vehicle’s Engine Control Module (ECM) or Powertrain Control Module (PCM) has detected that the crankshaft and Bank 2 “A” camshaft are no longer properly synchronized.
On most dual-overhead-cam engines, Sensor A refers to the intake camshaft, while Bank 2 is the side of the engine opposite Bank 1. Bank 1 contains cylinder number one, so Bank 2 is the other cylinder bank.
The crankshaft controls piston movement, while the intake camshaft controls when the intake valves open and close. These components must remain precisely synchronized for the engine to start, run efficiently and avoid internal damage.
P0018 is commonly caused by:
- A stretched timing chain
- A jumped or incorrectly installed timing chain
- A slipped or damaged timing belt
- A failed timing-chain tensioner
- Worn or broken timing guides
- A faulty Bank 2 intake camshaft phaser
- A sticking intake VVT solenoid
- Low or dirty engine oil
- Low engine-oil pressure
- A faulty camshaft or crankshaft position sensor
- A shifted or damaged reluctor wheel
- Incorrect mechanical timing
P0018 should be treated as a serious trouble code. Although a sensor or wiring fault can trigger it, the code often points to a mechanical timing or variable valve timing problem that can eventually cause major engine damage.
Looking for more diagnostic resources? Browse our complete OBD-II libraries:
- Complete OBD-II Code Library: https://my.prostreetonline.com/dtc-obdii/
- Body (B) Codes: https://my.prostreetonline.com/dtc-doctor/b-code-obd-ii-codes/
- Chassis (C) Codes: https://my.prostreetonline.com/dtc-doctor/c-code-obd-ii-codes/
P0018 Quick Facts
| Item | Information |
|---|---|
| OBD-II code | P0018 |
| Official description | Crankshaft Position–Camshaft Position Correlation Bank 2 Sensor A |
| Category | Powertrain |
| System | Mechanical engine timing and variable valve timing |
| Code type | Generic SAE powertrain code |
| Severity | High |
| Safe to drive? | Limited driving only; diagnose immediately |
| Most common causes | Stretched timing chain, failed tensioner, Bank 2 intake VVT fault |
| Typical repair cost | $150–$4,000+ |
What Does the P0018 Code Mean?
P0018 means “Crankshaft Position–Camshaft Position Correlation Bank 2 Sensor A.”
The ECM continuously compares the electrical signals produced by the crankshaft position sensor and the Bank 2 intake camshaft position sensor.
The crankshaft position sensor helps the ECM determine:
- Engine RPM
- Crankshaft speed
- Piston position
- Top-dead-center reference
- Ignition timing
- Fuel-injection timing
The camshaft position sensor helps the ECM determine:
- Intake camshaft position
- Valve-timing position
- Cylinder identification
- Variable valve timing response
- Camshaft synchronization
The ECM expects the crankshaft and Bank 2 intake camshaft signals to maintain a precise relationship.
When the Bank 2 intake camshaft signal occurs earlier, later or more inconsistently than expected relative to the crankshaft signal, the ECM stores P0018.
The timing deviation may be caused by:
- Mechanical chain or belt movement
- Variable valve timing malfunction
- Sensor signal distortion
- Reluctor-wheel movement
- Incorrect engine assembly
- Low oil pressure
P0018 is closely related to:
- P0016: Crankshaft Position–Camshaft Position Correlation Bank 1 Sensor A
- P0017: Crankshaft Position–Camshaft Position Correlation Bank 1 Sensor B
- P0019: Crankshaft Position–Camshaft Position Correlation Bank 2 Sensor B
- P0020: “A” Camshaft Position Actuator Circuit Bank 2
- P0021: “A” Camshaft Position Timing Over-Advanced Bank 2
- P0022: “A” Camshaft Position Timing Over-Retarded Bank 2
- P0009: Engine Position System Performance Bank 2
What Does Sensor A Mean?
On most dual-overhead-cam engines:
- Sensor A monitors the intake camshaft.
- Sensor B monitors the exhaust camshaft.
P0018 therefore usually refers to the relationship between the crankshaft and the Bank 2 intake camshaft.
On some engines, the manufacturer may use a different naming convention. Always verify the correct camshaft and sensor using vehicle-specific repair information.
Do not replace a sensor based only on its location on the cylinder head.
What Is Bank 2?
Bank 2 is the side of the engine that does not contain cylinder number one.
Bank 2 exists only on engines with more than one cylinder bank, such as:
- V6 engines
- V8 engines
- V10 engines
- V12 engines
- Horizontally opposed engines
Inline four-cylinder and inline six-cylinder engines have only Bank 1, so they generally cannot store a true Bank 2 code.
Bank 2 may be located on either the driver or passenger side, depending on the engine.
Confirm Bank 2 using:
- Manufacturer service information
- A cylinder-numbering diagram
- A firing-order diagram
- Underhood labels
- A professional repair database
Never assume Bank 2’s location based solely on vehicle orientation.
How Crankshaft and Intake Camshaft Timing Works
The crankshaft converts piston movement into rotational force.
The intake camshaft opens and closes the intake valves, allowing air or an air-fuel mixture to enter the cylinders.
The crankshaft and camshaft are connected through a:
- Timing chain
- Timing belt
- Gear drive
- Combination of chains and gears
During normal engine operation:
- The intake valve opens.
- The piston moves downward.
- Air and fuel enter the cylinder.
- The intake valve closes.
- The piston compresses the mixture.
- Combustion forces the piston downward.
- The exhaust valve opens.
- Exhaust gases leave the cylinder.
The intake valves must open and close at exactly the correct time relative to crankshaft position.
If the Bank 2 intake camshaft moves too far relative to the crankshaft, the engine may suffer:
- Poor cylinder filling
- Reduced compression
- Misfires
- Rough idle
- Hard starting
- Reduced power
- Increased emissions
- Internal engine damage
How the ECM Detects P0018
The camshaft and crankshaft position sensors monitor patterned reluctor wheels.
As each reluctor tooth or target passes the sensor, the sensor produces an electrical signal.
The ECM compares the timing of these signals with a programmed reference pattern.
The ECM may store P0018 when:
- The Bank 2 intake camshaft signal is too advanced.
- The camshaft signal is too retarded.
- The correlation error exceeds a programmed limit.
- The camshaft position changes unexpectedly.
- Signal edges do not align correctly.
- The intake camshaft phaser cannot return to its base position.
- A sensor signal becomes weak or distorted.
An oscilloscope can display the camshaft and crankshaft signals together. This is known as a cam and crank correlation waveform.
Comparing the waveform with a known-good pattern can help identify mechanical timing errors without immediately disassembling the engine.
Symptoms of the P0018 Code
Symptoms vary depending on how far the timing has shifted and whether the cause is mechanical, hydraulic or electrical.
Common symptoms include:
- Illuminated Check Engine Light
- Rough idle
- Engine misfires
- Poor acceleration
- Reduced engine power
- Engine hesitation
- Hard starting
- Extended cranking
- Engine stalling
- Poor fuel economy
- Increased exhaust emissions
- Timing-chain rattle
- Metallic startup noise
- Limp mode
- Failed emissions inspection
- Engine cranks but will not start
- Backfiring through the intake or exhaust
- Uneven engine operation
- Strong fuel or exhaust odor
A small correlation error may produce only a Check Engine Light.
A severely stretched or jumped timing chain may cause:
- Low compression
- Severe misfires
- A no-start condition
- Bent valves
- Damaged pistons
- Cylinder-head damage
Common Causes of P0018
1. Stretched Timing Chain
A stretched timing chain is one of the most common causes of P0018.
Timing chains do not normally stretch like rubber. Instead, wear develops at the:
- Chain pins
- Links
- Bushings
- Sprocket teeth
The accumulated wear increases the chain’s effective length and alters the relationship between the crankshaft and Bank 2 intake camshaft.
Common signs of timing-chain wear include:
- Startup rattling
- Poor acceleration
- Multiple camshaft timing codes
- Extended cranking
- Excessive camshaft phase error
- Timing marks that no longer align
- Excessive chain-tensioner extension
Timing-chain wear is more likely on engines with:
- High mileage
- Extended oil-change intervals
- Low oil levels
- Sludge buildup
- Incorrect oil viscosity
- Known timing-system weaknesses
2. Failed Timing-Chain Tensioner
The timing-chain tensioner keeps the chain tight.
Many tensioners rely on:
- Spring pressure
- Engine-oil pressure
- A mechanical ratcheting system
A failed tensioner can allow the chain to become loose and change camshaft timing.
Possible failures include:
- Weak internal spring
- Hydraulic leakage
- Internal wear
- Sludge restriction
- Mechanical collapse
- Loss of pressure after shutdown
A tensioner that drains down overnight often causes a brief rattling noise during startup.
3. Worn or Broken Timing Guides
Timing-chain guides keep the chain aligned.
They may:
- Crack
- Wear through
- Break apart
- Separate from their mounts
- Allow chain slapping
Broken guide material may fall into the oil pan and restrict the oil pickup.
This can create both:
- A mechanical timing problem
- A low-oil-pressure problem
4. Jumped Timing Chain
A loose timing chain may jump one or more sprocket teeth.
This can occur because of:
- Severe chain stretch
- A failed tensioner
- Broken timing guides
- Low oil pressure
- Engine kickback during starting
- Improper timing-system repairs
A chain that jumps one tooth may cause rough running and P0018.
A chain that jumps several teeth may cause:
- A no-start condition
- Bent intake valves
- Piston damage
- Cylinder-head damage
- Complete engine failure
5. Slipped or Damaged Timing Belt
On an engine using a timing belt, P0018 may be caused by:
- Worn belt teeth
- Missing belt teeth
- A failed tensioner
- A seized idler pulley
- Oil contamination
- Incorrect installation
- Excessive belt slack
Timing belts should be replaced according to the manufacturer’s specified interval.
A failed timing belt on an interference engine may cause immediate internal damage.
6. Incorrect Mechanical Timing
P0018 may appear after:
- Timing-chain replacement
- Timing-belt replacement
- Cylinder-head repairs
- Camshaft replacement
- Camshaft phaser replacement
- Engine rebuilding
Possible assembly mistakes include:
- Bank 2 intake camshaft installed one tooth off
- Crankshaft timing mark misaligned
- Incorrect marked chain links
- Camshaft phaser installed incorrectly
- Tensioner released improperly
- Wrong locking-tool procedure
- Incorrect replacement parts
- Engine rotated before timing was secured
If P0018 appears immediately after engine work, verify mechanical timing before replacing sensors.
7. Faulty Bank 2 Intake Camshaft Phaser
The intake camshaft phaser changes camshaft timing using engine-oil pressure.
A failed phaser may:
- Stick advanced
- Stick retarded
- Respond slowly
- Fail to return to its base position
- Leak oil internally
- Rattle during startup
- Develop excessive mechanical play
A phaser that remains in the wrong position can trigger P0018 even if the base timing chain alignment is correct.
Related codes may include:
- P0020
- P0021
- P0022
- P0009
8. Faulty Bank 2 Intake VVT Solenoid
The intake VVT solenoid controls oil flow to the Bank 2 camshaft phaser.
A sticking or failed solenoid may prevent the intake camshaft from reaching the expected position.
Possible causes include:
- Sludge contamination
- Metal debris
- Clogged filter screen
- Internal electrical failure
- Sticking valve mechanism
- Restricted oil flow
- Damaged connector
An electrical actuator fault may also store P0020.
Timing-performance faults may store P0021 or P0022.
9. Low Engine Oil Level
Variable valve timing systems and hydraulic chain tensioners depend on engine oil.
Low oil may cause:
- Weak timing-chain tension
- Delayed phaser response
- Inconsistent camshaft movement
- Startup rattling
- Low oil pressure
- Multiple VVT codes
Always check the oil level before beginning advanced diagnosis.
10. Dirty or Incorrect Engine Oil
Dirty or incorrect oil can interfere with both VVT operation and timing-chain tensioner performance.
Possible problems include:
- Sludge
- Varnish
- Carbon contamination
- Incorrect viscosity
- Fuel dilution
- Coolant contamination
- Metal particles
Oil that is too thick may flow too slowly through the Bank 2 intake phaser and solenoid.
Oil that is too thin may fail to maintain sufficient pressure in worn components.
11. Low Engine Oil Pressure
The engine-oil level may be correct while actual pressure remains too low.
Possible causes include:
- Worn oil pump
- Restricted oil pickup
- Excessive bearing clearance
- Internal oil leakage
- Clogged oil passages
- Failed pressure-control valve
- Damaged oil-pump drive
Low oil pressure can affect:
- Timing-chain tensioners
- Camshaft phasers
- VVT solenoids
- Camshaft position stability
A mechanical oil-pressure test may be required.
12. Faulty Bank 2 Camshaft Position Sensor
The Bank 2 intake camshaft position sensor may produce:
- A weak signal
- Intermittent dropout
- A distorted waveform
- Incorrect switching
- No signal
Possible causes include:
- Internal sensor failure
- Connector corrosion
- Broken wiring
- Metal debris on the sensor
- Incorrect sensor clearance
- Heat damage
However, the sensor may be functioning correctly and reporting a real timing problem.
Do not replace it based only on P0018.
13. Faulty Crankshaft Position Sensor
The crankshaft position sensor provides the ECM’s primary engine-position reference.
A faulty signal may be caused by:
- Internal sensor failure
- Damaged wiring
- Connector corrosion
- Incorrect air gap
- Heat damage
- Metal debris
- Excessive crankshaft movement
A crankshaft position sensor fault may also cause:
- Engine stalling
- Tachometer dropout
- Extended cranking
- No-start condition
- Additional sensor codes
14. Shifted Bank 2 Camshaft Reluctor Wheel
The Bank 2 intake camshaft sensor reads a reluctor or trigger wheel mounted on the camshaft or phaser.
The reluctor may become:
- Loose
- Bent
- Cracked
- Misaligned
- Shifted on the camshaft
- Damaged during previous repairs
A shifted reluctor changes the sensor signal even if the actual valve timing remains correct.
15. Shifted Crankshaft Reluctor Wheel
The crankshaft reluctor may also move out of position.
Possible causes include:
- Loose press fit
- Crankshaft damage
- Improper engine assembly
- Harmonic balancer failure
- Collision damage
- Excessive crankshaft end play
A shifted crankshaft reluctor can affect multiple camshaft correlation codes at once.
16. Damaged Sensor Wiring or Connectors
Inspect the Bank 2 camshaft and crankshaft sensor circuits for:
- Broken wires
- Loose connectors
- Corrosion
- Bent terminals
- Oil contamination
- Heat damage
- Harness abrasion
- Rodent damage
- Poor previous repairs
Intermittent wiring faults may occur only when the engine is hot, vibrating or under load.
17. Faulty ECM or PCM
ECM failure is possible but uncommon.
Before replacing the module, verify:
- Mechanical timing
- Camshaft and crankshaft signals
- Reluctor alignment
- Engine-oil pressure
- VVT operation
- Wiring continuity
- ECM power and ground circuits
A replacement ECM may require:
- Programming
- VIN configuration
- Immobilizer relearning
- Camshaft variation relearning
How Serious Is the P0018 Code?
P0018 is a serious diagnostic trouble code.
It may mean the engine’s mechanical timing is no longer correct.
Ignoring the code may lead to:
- Poor engine performance
- Increased fuel consumption
- Engine stalling
- Timing-chain failure
- Timing-belt failure
- Valve-to-piston contact
- Bent valves
- Damaged pistons
- Cylinder-head damage
- Complete engine failure
The risk is particularly high on an interference engine.
In an interference engine, the pistons and valves occupy the same physical space at different times. If the camshaft timing shifts far enough, the components may collide.
Can You Drive With P0018?
Limited driving may be possible if:
- The engine runs smoothly.
- No timing-system noise is present.
- Engine-oil pressure is normal.
- The Check Engine Light remains steady.
- The engine does not stall.
- Power remains normal.
However, continued driving is not recommended.
Stop driving immediately if you notice:
- Loud rattling from the timing cover
- Repeated startup clatter
- Severe engine misfires
- A flashing Check Engine Light
- Sudden power loss
- Backfiring
- Low-oil-pressure warning
- Engine stalling
- A no-start condition
If the timing chain or belt has moved, further operation may cause catastrophic engine damage.
How to Diagnose P0018
Step 1: Scan for Additional Codes
Use an OBD-II scanner to check for related codes.
Common companion codes include:
- P0008
- P0009
- P0016
- P0017
- P0019
- P0020
- P0021
- P0022
- Camshaft sensor codes
- Crankshaft sensor codes
- Misfire codes
- Oil-pressure codes
Record:
- Freeze-frame data
- Engine speed
- Engine load
- Coolant temperature
- Oil temperature
- Commanded Bank 2 intake camshaft angle
- Actual Bank 2 intake camshaft position
- Battery voltage
Do not clear the codes before recording this information.
Step 2: Check the Engine Oil
Inspect:
- Oil level
- Oil condition
- Oil viscosity
- Sludge
- Metal particles
- Fuel contamination
- Coolant contamination
Correct low or incorrect oil before proceeding.
Fresh oil may improve a sticking VVT system, but it cannot repair a stretched timing chain or slipped timing belt.
Step 3: Identify Bank 2 and Sensor A
Use vehicle-specific repair information to identify:
- Bank 2
- The intake camshaft
- Sensor A
- The Bank 2 VVT solenoid
- The camshaft phaser
- Connector pin locations
Do not assume Bank 2 is on a particular side of the vehicle.
Incorrect bank identification can lead to unnecessary parts replacement and wasted diagnostic time.
Step 4: Review Maintenance and Repair History
Determine:
- When the oil was last changed
- Whether the engine has been run low on oil
- Whether timing work was recently performed
- Whether the engine has a startup rattle
- Whether the timing belt is overdue
- Whether the engine was recently rebuilt
- Whether the Bank 2 intake phaser was replaced
A code appearing immediately after timing work strongly suggests an installation error.
Step 5: Listen for Timing-System Noise
Start the engine when cold and listen near the timing cover.
Warning sounds include:
- Brief startup rattle
- Continuous chain slapping
- Metallic ticking
- Scraping
- Noise that increases with engine speed
Cold-start rattling may indicate:
- Timing-chain slack
- Tensioner drain-down
- Worn guides
- Camshaft phaser failure
Keep hands, clothing and tools away from moving engine components.
Step 6: Inspect Sensor Wiring and Connectors
Inspect the Bank 2 intake camshaft and crankshaft sensor circuits.
Look for:
- Broken wires
- Loose connectors
- Corrosion
- Bent pins
- Oil contamination
- Heat damage
- Harness abrasion
- Poor previous repairs
Repair visible electrical faults before disassembling the engine.
Step 7: Test the Bank 2 Camshaft Position Sensor
Depending on sensor design, test:
- Power supply
- Ground
- Signal voltage
- Signal frequency
- Signal waveform
- Circuit continuity
Hall-effect sensors normally require:
- A reference voltage
- Ground
- A digital signal circuit
Magnetic sensors may generate their own AC voltage.
Use manufacturer specifications.
Step 8: Test the Crankshaft Position Sensor
Perform similar testing on the crankshaft position sensor.
Inspect:
- Sensor resistance when applicable
- Signal voltage
- Signal waveform
- Power and ground
- Connector condition
- Sensor air gap
An oscilloscope is often the best tool for detecting intermittent signal dropout.
Step 9: Compare Camshaft and Crankshaft Waveforms
Connect an oscilloscope to the Bank 2 intake camshaft sensor and crankshaft sensor.
Compare the signals with a known-good waveform.
This may identify:
- Timing-chain stretch
- Incorrect mechanical timing
- Shifted reluctor
- Sensor dropout
- Excessive camshaft movement
- Electrical interference
Waveform correlation can sometimes confirm a mechanical timing problem without removing the timing cover.
Step 10: Monitor Bank 2 Intake Camshaft Position
Use a capable scan tool to compare:
- Commanded intake camshaft angle
- Actual intake camshaft angle
- Camshaft phase error
- Intake VVT solenoid duty cycle
- Camshaft response time
A camshaft that remains consistently advanced or retarded may indicate:
- Mechanical timing error
- Chain stretch
- A sticking phaser
- Restricted oil flow
- Low oil pressure
Compare Bank 2 data with Bank 1 when the engine design allows it.
A major difference between the banks can be a useful diagnostic clue.
Step 11: Test the Bank 2 Intake VVT Solenoid
Inspect and test the Bank 2 intake VVT solenoid.
Testing may include:
- Solenoid resistance
- Power-supply testing
- ECM control testing
- Current measurement
- Bidirectional activation
- Inspection for sludge or debris
If the electrical circuit works but the camshaft does not move correctly, suspect a hydraulic or mechanical problem.
Step 12: Remove and Inspect the VVT Solenoid
Remove the solenoid according to the manufacturer’s service procedure.
Inspect it for:
- Sludge
- Metal debris
- Clogged screens
- Varnish
- Damaged O-rings
- Sticking valve movement
- Physical damage
Heavy metal contamination may indicate timing-chain, camshaft phaser or internal engine wear.
Step 13: Check Engine Oil Pressure
Install a mechanical oil-pressure gauge if low pressure is suspected.
Measure pressure at:
- Cold idle
- Warm idle
- Increased engine speed
Compare the readings with factory specifications.
Do not assume oil pressure is adequate simply because the dashboard warning light remains off.
Step 14: Compare Bank 1 and Bank 2 Operation
On engines with similar intake VVT systems on both banks, compare:
- Commanded camshaft position
- Actual camshaft position
- Response time
- VVT solenoid duty cycle
- Camshaft phase error
If Bank 1 operates normally while Bank 2 remains out of position, the fault is likely localized to:
- Bank 2 timing components
- Bank 2 oil passages
- Bank 2 VVT solenoid
- Bank 2 camshaft phaser
- Bank 2 sensor or reluctor
Step 15: Verify Mechanical Timing
If scan data or waveform testing suggests a timing fault, inspect the mechanical timing system.
This may require removing:
- Valve covers
- Timing covers
- Front-engine accessories
- Engine mounts
- Camshaft access plugs
Position the engine at top dead center and compare all timing marks with factory specifications.
Inspect:
- Timing-chain slack
- Timing-belt alignment
- Chain tensioner extension
- Guide condition
- Sprocket wear
- Bank 2 intake camshaft phaser position
- Crankshaft alignment
- Camshaft alignment
Special camshaft and crankshaft locking tools may be required.
Step 16: Inspect the Reluctor Wheels
If mechanical timing is correct but correlation remains wrong, inspect the camshaft and crankshaft reluctors.
Look for:
- Shifted position
- Cracks
- Bent teeth
- Missing segments
- Loose mounting
- Damage from previous repairs
Some reluctors are press-fit and may require replacement of the camshaft, phaser or crankshaft if they move.
Step 17: Check Technical Service Bulletins
Some engines have known problems involving:
- Timing-chain stretch
- Revised tensioners
- Updated intake camshaft phasers
- Bank-specific oil-flow restrictions
- Reluctor-wheel movement
- Updated engine-oil specifications
- ECM software
- Extended warranty coverage
- Revised diagnostic procedures
Review manufacturer service information before beginning major repairs.
Step 18: Verify the Repair
After completing repairs:
- Clear all stored codes.
- Start the engine from cold.
- Listen for abnormal timing-system noise.
- Monitor camshaft and crankshaft synchronization.
- Compare commanded and actual Bank 2 intake camshaft position.
- Complete the manufacturer’s drive cycle.
- Rescan for pending codes.
- Restart the engine several times.
A successful repair should restore proper correlation and prevent P0018 from returning.
Common P0018 Repairs and Costs
| Repair | Estimated cost |
| Diagnostic inspection | $100–$300 |
| Engine oil and filter change | $60–$180 |
| Repair sensor wiring | $100–$500 |
| Replace Bank 2 intake camshaft position sensor | $150–$450 |
| Replace crankshaft position sensor | $175–$500 |
| Replace Bank 2 intake VVT solenoid | $150–$500 |
| Replace Bank 2 intake camshaft phaser | $600–$1,800 |
| Replace timing-belt kit | $700–$2,000 |
| Replace timing-chain tensioner | $500–$1,500 |
| Replace timing chain, guides and tensioners | $1,200–$4,000 |
| Repair cylinder-head damage | $2,500–$6,000+ |
| Replace engine | $4,000–$12,000+ |
| ECM software update | $100–$300 |
| Replace and program ECM | $1,000–$2,500+ |
Repair cost depends on:
- Engine design
- Component accessibility
- The number of timing chains
- Whether the engine must be removed
- Whether valve damage occurred
- Whether components on both banks are replaced
A sensor replacement should not be assumed until the mechanical timing and VVT system have been evaluated.
Common Diagnostic Mistakes
Replacing the Bank 2 Camshaft Sensor Immediately
P0018 does not automatically mean the camshaft position sensor has failed.
The sensor may be accurately reporting that the Bank 2 intake camshaft is out of time.
Replacing the Crankshaft Sensor Without Testing It
Replacing the crankshaft sensor without checking timing correlation may waste time and money.
Confusing Bank 1 and Bank 2
Bank 1 contains cylinder number one.
Bank 2 is the opposite bank.
Incorrect bank identification can lead to testing or replacing the wrong sensor, solenoid or phaser.
Confusing Sensor A and Sensor B
Sensor A usually refers to the intake camshaft.
Sensor B usually refers to the exhaust camshaft.
Always confirm manufacturer terminology.
Ignoring Timing-Chain Noise
Startup rattling is an important diagnostic clue.
It may indicate:
- Chain stretch
- Tensioner failure
- Timing-guide wear
- Camshaft phaser failure
Ignoring the noise can lead to severe engine damage.
Assuming an Oil Change Will Repair Mechanical Wear
Fresh oil may improve a sticking VVT solenoid or hydraulic phaser.
It cannot repair:
- A stretched timing chain
- Missing timing-belt teeth
- Broken guides
- A failed tensioner
- A shifted reluctor
- Incorrect mechanical timing
Ignoring Recent Engine Repairs
If P0018 appears after timing-chain, timing-belt, camshaft or cylinder-head work, verify the installation before replacing electrical components.
Skipping Oil-Pressure Testing
Low oil pressure can affect both the Bank 2 camshaft phaser and timing-chain tensioner.
A correct oil level does not guarantee adequate oil pressure.
Failing to Compare Both Banks
Comparing Bank 1 and Bank 2 camshaft data can reveal whether the problem is isolated to one side of the engine.
Failing to Inspect the Reluctor Wheel
A shifted reluctor can cause a persistent correlation code even when the mechanical timing marks appear correct.
Replacing the ECM Too Early
ECM failure is much less common than:
- Timing-chain wear
- Incorrect timing
- VVT faults
- Sensor problems
- Wiring damage
- Reluctor movement
Test the complete system before replacing the module.
Vehicles Commonly Affected by P0018
P0018 can appear on OBD-II vehicles with multiple cylinder banks and separate camshaft and crankshaft position sensors.
Potentially affected manufacturers include:
- Chevrolet
- GMC
- Buick
- Cadillac
- Ford
- Lincoln
- Chrysler
- Dodge
- Jeep
- Toyota
- Lexus
- Honda
- Acura
- Nissan
- Infiniti
- Hyundai
- Kia
- BMW
- Mini
- Mercedes-Benz
- Volkswagen
- Audi
- Porsche
- Subaru
- Volvo
- Mitsubishi
P0018 is commonly associated with engines using:
- V6 or V8 layouts
- Timing chains
- Hydraulic chain tensioners
- Dual-overhead camshafts
- Intake variable valve timing
- Oil-controlled camshaft phasers
- Press-fit reluctor wheels
The code alone does not prove that a specific vehicle has a known defect.
Diagnosis must be based on the exact year, make, model, engine and maintenance history.
How to Prevent P0018
Helpful preventive measures include:
- Check the engine oil regularly.
- Use the manufacturer-specified oil viscosity.
- Change the oil and filter on schedule.
- Avoid extended oil-change intervals.
- Use a quality oil filter.
- Repair oil leaks promptly.
- Investigate excessive oil consumption.
- Replace timing belts at the required interval.
- Address startup rattles immediately.
- Diagnose low-oil-pressure warnings promptly.
- Use complete timing-component kits when appropriate.
- Replace worn components on both banks when recommended.
- Follow exact mechanical timing procedures.
- Use required camshaft and crankshaft locking tools.
- Replace one-time-use bolts and seals.
- Verify all timing marks before startup after repairs.
Good oil maintenance is especially important on engines using hydraulic timing-chain tensioners and oil-controlled camshaft phasers.
Frequently Asked Questions About P0018
What does code P0018 mean?
P0018 means the ECM has detected that the Bank 2 intake camshaft and crankshaft are not properly synchronized.
Is Sensor A the intake camshaft?
On most engines, yes.
Sensor A usually refers to the intake camshaft, while Sensor B usually refers to the exhaust camshaft.
Which side is Bank 2?
Bank 2 is the side of the engine that does not contain cylinder number one.
Its physical location varies by engine.
Can an inline engine have a P0018 code?
Normally, no.
Inline engines have only one cylinder bank. P0018 is intended for engines with a Bank 2, such as V6, V8 or horizontally opposed engines.
Is P0018 usually caused by a timing chain?
A stretched or jumped timing chain is one of the most common causes.
However, P0018 can also be caused by:
- A damaged timing belt
- Bank 2 intake VVT problems
- Sensor faults
- Wiring damage
- A shifted reluctor wheel
Can low oil cause P0018?
Yes. Low oil may reduce pressure to the timing-chain tensioner and Bank 2 intake camshaft phaser.
Can dirty oil cause P0018?
Yes. Dirty oil may restrict the Bank 2 VVT solenoid, camshaft phaser or timing-chain tensioner.
Can the wrong oil viscosity cause P0018?
Yes. Incorrect oil viscosity can affect VVT response and hydraulic timing-chain tensioner operation.
Can a bad Bank 2 camshaft sensor cause P0018?
Yes, but the sensor should be tested before replacement.
It may be accurately reporting an actual mechanical timing problem.
Can a bad crankshaft sensor cause P0018?
Yes. A distorted or intermittent crankshaft signal may create an incorrect correlation reading.
Can a bad Bank 2 VVT solenoid cause P0018?
Yes. A sticking solenoid may prevent the intake camshaft from reaching its expected position.
Can a bad camshaft phaser cause P0018?
Yes. A worn or sticking Bank 2 intake phaser may remain advanced or retarded and trigger a correlation fault.
Can a shifted reluctor wheel cause P0018?
Yes. A shifted camshaft or crankshaft reluctor can change the sensor signal even when mechanical timing appears correct.
Can I drive with P0018?
Limited driving may be possible if the engine runs normally and makes no unusual noise.
However, continued driving is risky because the code may indicate a loose or jumped timing chain.
Can P0018 cause rough idle?
Yes. Incorrect Bank 2 intake camshaft timing can cause rough idle, misfires and poor acceleration.
Can P0018 cause a no-start condition?
Yes. If the timing chain or belt moves far enough, the engine may crank but fail to start.
Will an oil change fix P0018?
It may help if the problem is caused by dirty oil or a sticking VVT component.
It will not repair a stretched chain, damaged belt, broken guide, failed tensioner or shifted reluctor.
Does P0018 mean the engine is damaged?
Not necessarily.
However, operating the engine with incorrect mechanical timing can eventually cause internal damage, especially on an interference engine.
How much does it cost to fix P0018?
A sensor, wiring or VVT solenoid repair may cost a few hundred dollars.
A timing-chain repair may cost approximately $1,200 to $4,000 or more.
If valves or pistons are damaged, repair costs can exceed $5,000.
Will clearing P0018 fix the vehicle?
No. Clearing the code only removes the warning temporarily.
The code will return if the camshaft and crankshaft correlation problem remains.
Will P0018 fail an emissions test?
Yes. An active Check Engine Light or emissions-related powertrain code will generally cause an OBD-based emissions inspection failure.
Final Thoughts
The P0018 code means the Bank 2 intake camshaft and crankshaft are no longer properly synchronized.
The most common causes include:
- A stretched or jumped timing chain
- A damaged or incorrectly installed timing belt
- A failed timing-chain tensioner
- Worn timing guides
- Low or dirty engine oil
- Low engine-oil pressure
- A sticking Bank 2 intake VVT solenoid
- A failed Bank 2 intake camshaft phaser
- A faulty camshaft or crankshaft sensor
- A shifted reluctor wheel
- Incorrect mechanical timing
Begin diagnosis by checking the engine-oil level and condition, scanning for related codes and confirming the location of Bank 2 and Sensor A.
Inspect the sensor wiring and compare the camshaft and crankshaft signals. If the signals indicate a genuine correlation error, verify oil pressure, Bank 2 intake VVT operation and mechanical timing before replacing sensors or the ECM.
P0018 should be diagnosed promptly. Addressing it early may prevent a manageable VVT or timing-system repair from becoming a complete engine replacement.
For more diagnostic guides, browse our growing OBD-II libraries:
- Complete OBD-II Code Library: https://my.prostreetonline.com/dtc-obdii/
- Body (B) Codes: https://my.prostreetonline.com/dtc-doctor/b-code-obd-ii-codes/
- Chassis (C) Codes: https://my.prostreetonline.com/dtc-doctor/c-code-obd-ii-codes/
