There are quite a few things that can go wrong with the camshaft and crankshaft that result in the setting of a diagnostic trouble code (DTC). The DTC P0018 is one of the trouble codes that indicate an issue with the relationship between the camshaft and crankshaft. Find out more about this trouble code with this informative guide.
What Does the P0018 Code Mean?
Diagnostic trouble code (DTC) P0018 stands for “Crankshaft Position- Camshaft Position Correlation (Bank 2, Sensor A).” It is set when the camshaft(s) on bank 2 of the engine is not in its proper position in relation to the crankshaft. The “Bank 2” in this definition refers to the side of the engine that does not contain the number one cylinder. Meanwhile, the “Sensor A” refers to the intake camshaft sensor.
The ECM/PCM detects any out-of-time situation involving the crankshaft and camshaft (for example, greater than 9 degrees on a GM) and sets trouble codes like P0018 and others listed below.
Here are other codes GM uses with a similar meaning:
- DTC P0016 Crankshaft Position – Intake Camshaft Position Not Plausible Bank 1
- DTC P0017 Crankshaft Position – Exhaust Camshaft Position Not Plausible Bank 1
- DTC P0018 Crankshaft Position – Intake Camshaft Position Not Plausible Bank 2
- DTC P0019 Crankshaft Position – Exhaust Camshaft Position Not Plausible Bank 2
The crankshaft position sensor (CKP) and the camshaft position sensor (CMP) work together to ensure that your engine runs smoothly. The CKP monitors the speed and position of the crankshaft, while the CMP monitors the speed and position of the camshaft(s). These two sensors each read an individual reluctor or tone ring. For the CKP, this ring is usually mounted on the crankshaft or on the harmonic balancer. For the CMP, this ring is located on the camshaft itself, or the camshaft sprocket.
The PCM uses the information it gets from the CMP and compares it with the information from the CKP. This helps the PCM determine if the engine is timed properly.
If you plan on fixing P0018 yourself, you should read our advanced technical discussion about the camshaft and crankshaft.
Note: The definition of OBD-II codes may vary depending on the vehicle manufacturer. For more information on P0018 and how it applies to your vehicle, you can consult a repair manual or database.
What are the Possible Causes of the P0018 Code?
Below is a list of the most probable reasons why the P0018 engine code registers in your vehicle’s memory. If your car has an engine with variable valve timing, keep in mind that it’s a potential cause of camshaft and crankshaft correlation issues. Note that pinpointing the exact root cause will be helpful in diagnosis and repair. It will also help you avoid costly repairs due to inaccurate troubleshooting.
- Camshaft variable timing solenoid failure
- Low engine oil level
- Incorrect engine timing
- Engine oil doesn’t meet the manufacturer’s requirements
- Variable valve timing actuator failure
- Worn timing chain
- Failed timing chain tensioner or guides
- Damaged or shifted crankshaft reluctor wheel
What are the Common Symptoms of the P0018 Code?
You might notice the following symptoms in your vehicle if you’re dealing with P0018. Note that if you experience drivability problems, you may need to have your vehicle checked immediately at your nearest mechanic.
- Engine light on
- Decreased engine performance
- Engine hard to start
- No starting
- Engine stall while driving
- Engine running erratically, rough riding, hesitating
- Increased fuel consumption
- Rattling noise from the engine
How to Diagnose the P0018 Code
Diagnosing most OBD-II codes might be a challenge for many since there are a handful of possible causes for each code. The same goes for the P0018 engine code.
However, there are a lot of reliable resources you can use in order to assess the situation on your own. Repair manuals and databases are the best choices, especially for seasoned DIYers. There are also other sources you can use, such as online guides and informational videos. Below is a useful video resource if you want to know more about the P0018 code:
How to Fix the P0018 Code
Arriving at a long-term solution for any OBD-II code might be a challenge because you’ll need to pinpoint the exact root cause out of many possible causes. Also, vehicles are oriented and built differently, depending on the manufacturer. Repair procedures will inevitably vary. There is no single solution to OBD-II codes, P0018 included.
The best thing you can do is consult a reliable resource like a repair manual or a database. However, if you’re not confident in your repair and DIY skills, you should have a professional mechanic or technician do the troubleshooting and repairs for you to avoid costly mistakes and damage down the line.
Other Notes About P0018 Code
P0018 has both high repair importance and difficulty. One of the more common P00018 fixes is replacing the timing chain and other related components. However, this solution may not apply to every situation since there are a handful of other possible causes for this trouble code.
This issue is a bit more common in GM vehicles, and so there are technical service bulletins (TSBs) released to address the issue. The recommended fix for some vehicles with the P0018 code is replacing the crankshaft with a damaged reluctor wheel. Most professional mechanics and technicians recommend following the recommended motor oil type and service interval to avoid problems like this error code.
Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic.