This is one of the most frequent OBD2 trouble codes. Read the full article below to know what it means, how to fix it, and what other codes may show related to it.
This DTC (Diagnostic Trouble Code) refers to a problem with the vehicle’s camshaft position sensor A for Bank 2, where it doesn’t correlate to the crankshaft position sensor signal.
The Crankshaft Position Sensor (CKP) is a permanent magnet generator called a variable reticence sensor. The sensor magnetic field is changed by a reactor wheel attached to a crankshaft.
The Camshaft Position Sensor (CMP) is used to determine the crankshaft position(s). The CKP and CMP function in harmony to manage the supply of spark/fuel and the timing. The CKP and CMP are a ring or tone that travels through a magnetic sensor and creates a voltage which indicates position.
The CKP sensor sends data to the PCM or possibly the ignition module about the crankshaft position and engine RPM. The PCM will utilise this data to control the ignition timing and fuel injection. The data shows that the crankshaft sensor is the primary ignition trigger. It monitors the crankshaft position and communicates it to the PCM, which verifies the spark timing and initiates the injection process. The timing belt or chain connects the crescent shaft and camshaft to the sensors. Both should be exactly timed. The error code arises if the PCM detects a timing issue on either the crankshaft or the camshaft. Bank 2 has no cylinder 1, however sensor "A" is the camshaft side of the intake.
The common reasons for code P0018 are:
- Failure of the camshaft variable timing solenoid
- Engine oil level is too low
- Engine timing is incorrect.
- Engine oil does not conform to the specifications of the manufacturer.
- Failure of the variable valve timing actuator
- Timing chain that has become worn
- Timing chain tensioner or guides failure
- Crankshaft reluctor wheel that has been damaged or moved
Error code P0018 generally has several symptoms.
- Malfunction Indicator Lamp (MIL) gets illuminated.
- Although the engine will start and run, it will perform quite poorly.
- Normal idle noise, but considerable acceleration and power loss
- Engine rattles at the harmonic balancer, implying that the tone ring has been damaged.
- Fuel mileage reduction
- The engine is behaving strangely, riding rough, or hesitating.
Typically, an inspector begins diagnosing this error code by visually inspecting all of the connections and cabling for the camshaft sensors and OCV (Oil Control Valve). The following steps are involved in diagnosing the DTC P0018 code error.
- Evaluate the sensor's output
- Perform the permanent magnet sensor test after consulting the manufacturer's maintenance instructions.
- Determine which pin on the sensor connection is the signal return wire using the repair instructions for your car. Back probe the sensor wire with your multimeter set to DC voltage. Connect the black multimeter cable to the battery's ground terminal. When you crank the engine, the voltage readout on the metre should vary.
- Test the sensor synchronization
P0018 is both important and tough to repair. One of the most frequent P00018 solutions is to replace the timing chain and other associated components. However, this remedy may not apply to all situations because this problem code has a few other probable reasons.
How Serious is This?
- The engine might experience stalling, slowdown, and hard starting issues.
- If the valves strike the pistons, the timing chain, tensioners, or guides may be defective.
- Out of date camshafts can cause carbon buildup on engine piston rings and valves, requiring an engine rebuild due to lack of compression.
What Repairs Can Fix the Code
- First, the cam and crank sensors and their harnesses visually examine for damage. If you see damaged/broken wires, fix and check.
- Check the cam and crank patterns if you have access to a scope. Suspect a wrong sensor or sliding tonal ring if a pattern is absent. Remove the cam gear and the shaft balancer to ensure correct alignment and make sure that the rings are not loose or broken or that the key that lines them is not scraped. Substitute the sensor if correctly placed.
- If the signal seems to be normal, verify the correct alignment of the timing chain/belt. If it is misaligned, look for a broken tensioner that might have caused a tooth or many teeth to slide the chain/cord. Check also that the belt is not strained. Repair and verification.
- DTC: P0010 “A” Camshaft Position Actuator Circuit (Bank 1)
- DTC: P0011 “A” Camshaft Position – Timing Over-Advanced or System Performance (Bank 1)
- DTC: P0012 “A” Camshaft Position – Timing Over-Retarded (Bank 1)
- DTC: P0013 “B” Camshaft Position – Actuator Circuit (Bank 1)
- DTC: P0014 “B” Camshaft Position – Timing Over-Advanced or System Performance (Bank 1)
- DTC: P0015 “B” Camshaft Position -Timing Over-Retarded (Bank 1)
- DTC: P0016 Crankshaft Position – Camshaft Position Correlation (Bank 1 Sensor A)
- DTC: P0017 Crankshaft Position – Camshaft Position Correlation (Bank 1 Sensor)
- DTC: P0018 Crankshaft Position – Camshaft Position Correlation (Bank 2 Sensor A)
- DTC: P0019 Crankshaft Position – Camshaft Position Correlation (Bank 2 Sensor )
- DTC: P0020 “A” Camshaft Position Actuator Circuit (Bank 2)
- DTC: P0021 “A” Camshaft Position – Timing Over-Advanced or System Performance (Bank 2)
- DTC: P0022 “A” Camshaft Position – Timing Over-Retarded (Bank 2)
- DTC: P0023 “B” Camshaft Position – Actuator Circuit (Bank 2)
- DTC: P0024 “B” Camshaft Position – Timing Over-Advanced or System Performance (Bank 2)
- DTC: P0025 “B” Camshaft Position – Timing Over-Retarded (Bank 2)
The DTC P0018 code error is difficult to solve at home. An experienced mechanic is required to diagnose and fix this error. This may cause serious damage to the vehicle and its performance. A mishandled error may cause serious damage to the vehicle and one pocket.
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