Camshaft Position Sensor Bank 1: Where Is It?

Wondering what “Camshaft Position Sensor Bank 1” means? We’re guessing you have a P0017 trouble code in your car. This is just one of many trouble codes that indicate that you have a camshaft position sensor issue.

A camshaft position sensor—or CMP for short—trouble code is not to be taken lightly. It’s crucial for your engine’s smooth operation and can lead to severe damage if ignored. Here’s everything you need to know:

• What Is A Camshaft?
• Camshaft Position Sensor Location
• Signs Of A Bad Camshaft Sensor
• Causes & Diagnosis Of A Bad Sensor
• Sensor Repairs & Cost
• Frequently Asked Questions (FAQ)
• Wrap Up

What Is A Camshaft

If you’re unfamiliar with the camshaft and how an internal combustion engine works, stick around cause you need to know how it works and why it’s crucial. If you already have a good understanding, then you can skip the next section.

First, the basics: your car’s engine runs by burning fuel and air inside the cylinders. Once the fuel and air mixture combusts, it will force the piston inside the cylinder to move down and rotate a crankshaft underneath the engine.

The crankshaft converts the reciprocating motion of the pistons into a rotational motion. And then this force is transferred to the driven wheels through a series of gears and shafts. That’s essentially how a car works.

Back to that fuel and mixture, it needs to enter the cylinders at the right time. Specifically, during the intake stroke where the piston is moving down to allow space for the mixture before compressing it. The mixture enters the cylinder through valves, known as the intake valves.

The valves are closed by default, so how do you open them? With the help of the camshaft. The camshaft is a rotating shaft with lobes (cams) attached to it. These lobes rotate along with the shaft, and when the lobes come into contact with the intake valve, it will push the valve down to allow fuel and air to enter.

Note there are also exhaust valves in an engine. The exhaust valve works the same way as the intake valve—by using the camshaft to open them. But as the name suggests, the exhaust valves open when the engine needs to expel exhaust gases after combustion.

Camshaft Position Sensor

So, what does the camshaft position sensor do then? Before we explain further, what you should know is that the camshaft and crankshaft are connected via a timing belt or chain, depending on the car’s make and model.

The timing belt/chain is necessary because the camshaft and crankshaft need to be in rhythm. The crankshaft’s position determines the position of the pistons inside the engine, and what stroke of the combustion process each cylinder is in.

By timing the camshaft and crankshaft together with a timing belt/chain, the camshaft can open the correct valves at the correct time. For example, if cylinder 1 is in the exhaust stroke, then a correctly timed camshaft will open the exhaust valves to allow the exhaust gases to escape.

The camshaft position sensor’s (CMP) role is to determine the camshaft’s position as it relates to the crankshaft. If the timing is off, the CMP will know and can throw a trouble code to alert the driver that something is wrong with the engine.

The CMP sensor also helps the Engine Control Unit (ECU) to control the fuel injectors and ignition timing. It helps to make sure that these devices work correctly at the right time.

If the timing is off or the CMP is faulty, then the ECU can’t control the engine correctly. This can also cause the camshaft to open the valves at the wrong time, which can lead to severe damage. In interference-type engines, this often leads to complete engine failure.

Camshaft Position Sensor Bank 1 Location

So, now you know how a camshaft and its position sensor work. Where exactly is that camshaft position sensor bank 1? Camshaft position sensor bank 1 refers to the sensor in bank 1 of your engine. Okay, that’s pretty self-explanatory, let us explain further:

If you have an inline engine such as an inline-four or inline-six engine, then there’s only one cylinder bank (one row of cylinders). You don’t need to identify the banks, and all you need to do now is find the exact location of the sensor which varies depending on your car’s make and model.

If you have a V-configuration engine, such as a V6, V8, and so on, then you have two cylinder banks or two rows of engine cylinders. This means that each bank has its own camshaft and camshaft position sensor. Bank 1 is always the bank that has cylinder number 1, and the location varies depending on the car’s make and model.

For example, most Ford V8 engines have cylinder number 1 on the passenger side (left side when viewed from the front of the car). This means that’s bank 1, and that’s where the CMP sensor the code is referring to is located.

Meanwhile, most Chevy V8s have cylinder number 1 on the driver’s side. This means that bank 1 is on the driver’s side, and that’s where the CMP sensor you’re looking for is. Note that since each bank has its own camshaft, so it has at least one sensor each.

Crankshaft Position Camshaft Position Correlation Bank 1 Sensor A

In addition to the cylinder bank location, many cars have two sensors on each bank of the engine. The car’s OBD system will refer to the two sensors as sensor “A” and sensor “B”.

This is because most engines nowadays use DOHC (Dual Overhead Cam) technology. As the name suggests, this technology utilizes two camshafts on the engine; one for the intake valves, and one for the exhaust valves.

Since there are two camshafts, the engine needs two CMP sensors to know the position of each camshaft. Sensor “A” usually refers to the camshaft for the intake valves. Meanwhile, sensor “B” is located on the exhaust side of the cylinder head. If the exhaust manifold is on the driver’s side of the engine, that’s where sensor B is.

The sensor is usually a black plastic plug that connects to the engine’s cylinder head (the top part of the engine). You’ll see a connector and some wiring that connects it, usually to the car’s ECU.

Of course, the exact location of the sensor varies depending on your car’s make and model. So, we recommend checking your service manual to find the exact location of the sensor. But now you have a general idea of where the sensors are and where to find them.

Camshaft Position Sensor Symptoms

Regardless of what triggered the trouble code indicating your camshaft position sensor issue, it’s not to be taken lightly. Even if the cause isn’t too serious, an error with the CMP sensor can cause driving issues and severe damage in the long run. Here are the symptoms you have a CMP sensor problem:

Camshaft Position Sensor Bank 1, Symptoms #1: Engine Misfires And Performance Issues

As mentioned, the CMP sensors help the ECU to control various engine components including the fuel injectors and ignition timing. If the CMP is faulty or isn’t in sync with the crankshaft position sensor (CKP), this will give the ECU erroneous readings.

As a result, the ECU won’t be able to inject fuel into the engine and/or ignite it at the correct timing. Resulting in performance issues such as engine misfires (for more insight, check out our guide on how to fix engine misfire and the Dodge P0300 code) and poor acceleration.

This performance issue will often feel like the car is hesitating to accelerate. When you press the gas pedal, a good engine should accelerate and the RPM should climb with no problem whatsoever. But a faulty CMP sensor can cause the RPM to become unstable, or sometimes the car feels like it’s just not as fast as it usually is.

This can also manifest in the car being unable to start. Since it can ruin the ignition timing, the spark plugs will not fire and combust the fuel and air mixture at the right time, causing your car to crank but won’t start.

Causes and Reasons:

• Incorrect Sensor Readings – The main cause of engine misfires and performance issues due to a faulty CMP sensor is the incorrect readings it sends to the ECU. These readings play a crucial role in managing ignition timing and fuel injection.
• Age and Wear – Over time, like any electronic component, the CMP sensor can degrade due to the intense heat and demanding environment it operates in.
• Damaged Wiring – Wires connected to the sensor can fray or become damaged, disrupting the signal.

Diagnosis and Troubleshooting:

• Use of OBD-II Scanner – A scanner can detect specific error codes related to the CMP sensor, offering a quick initial diagnosis.
• Visual Inspection – A look at the sensor and the wires connected to it can reveal physical damage or wear.
• RPM Behavior – Observing the RPM while the engine is running can give hints on the sensor’s condition. Erratic behavior often points to faulty readings.

DIY Repairs/Fixes:

• Replace the Sensor – If faulty, replacing the CMP sensor is often the most effective solution.
• Repair Damaged Wiring – If the issue stems from damaged wiring, it can be repaired or replaced.

Repair/Replacement Costs:

• CMP Sensor Replacement – A typical camshaft position sensor can range from $50 to $250. However, prices vary based on car model and brand.
• Labor Costs – The labor can vary from $70 to $200 depending on your location and the complexity of the replacement.
• Diagnostic Fees – Mechanics might charge an initial $50 to $100 diagnostic fee.

Camshaft Position Sensor Bank 1, Symptoms #2: Engine Stalling

Your engine might also stall while you’re driving if you have a CMP sensor-related issue. This can be caused by a fuel injector that isn’t injecting fuel into the engine at the right time, or spark plugs not firing.

In severe cases, it might be because the engine has completely failed due to incorrect camshaft timing. In interference engines, incorrect timing between the camshaft and crankshaft can cause the pistons to come into contact with the valves.

Not only does this damage the pistons, but it will also bend the valves. Once this happens, the valves won’t be able to close properly and your engine will seize to work. This type of damage will often require a full engine rebuild.

Causes and Reasons:

• Erroneous Timing Controls – A faulty CMP can disrupt optimal engine timing, leading to stalls.
• Interference with Other Systems – The wrong timing can cause interference between pistons and valves, especially in interference engines.

Diagnosis and Troubleshooting:

• Stalling Observations – Does the engine stall during specific situations like accelerating or at idle? Patterns can point to CMP issues.
• OBD-II Scanner – Again, a scanner can detect error codes pointing directly or indirectly to CMP issues.

DIY Repairs/Fixes:

• Check Electrical Connections – Ensure that the sensor is properly connected and that there are no loose wires.
• Sensor Replacement – If the CMP sensor is the confirmed culprit, replace it.

Repair/Replacement Costs:

• Engine Rebuild (in severe cases) – The price can soar from $1,000 to $4,000 depending on the extent of damage and engine type.
• Labor Costs – For an engine rebuild, labor can significantly increase, ranging from $500 to $2,500.

Camshaft Position Sensor Bank 1, Symptoms #3: Worse Fuel Consumption

Again, since the CMP sensor affects how the ECU controls the fuel injectors, it can result in bad fuel mileage. Erroneous readings may cause the ECU to inject more fuel into the engine, resulting in higher fuel consumption when it isn’t necessary.

Causes and Reasons:

• Over-fueling – A malfunctioning CMP sensor can cause the ECU to inject more fuel than necessary, leading to wastage.
• Erroneous ECU Readings – Incorrect readings from the CMP sensor misguide the ECU in determining the fuel needs of the engine.

Diagnosis and Troubleshooting:

• Fuel Economy Records – Keep track of your miles per gallon (MPG). A noticeable drop without other reasons can indicate a CMP issue.
• OBD-II Scanner – Diagnostic tools can quickly identify if the sensor is causing fuel inefficiency.

DIY Repairs/Fixes:

• Check for Leaks – While not directly related, ensuring there’s no fuel leak can help improve fuel consumption.
• Replace CMP Sensor – A direct approach to resolving the issue if the sensor is faulty.

Repair/Replacement Costs:

• CMP Sensor Replacement – As previously mentioned, a CMP sensor can cost between $50 to $250.
• Labor Costs – Labor costs for this specific issue remain consistent at $70 to $200.
• Additional Fuel Costs – A malfunctioning CMP sensor might lead to extra fueling costs, which vary based on individual driving habits and fuel prices.

Camshaft Position Sensor Bank 1, Symptoms #4: Rough Idling

One symptom of a faulty camshaft position sensor is rough idling. Typically, when you start the car, the engine should run smoothly, with consistent RPMs. However, when the CMP sensor is malfunctioning, the engine may experience uneven or erratic RPM fluctuations. This can lead to vibrations or shaking sensations when your car is stationary. In more pronounced cases, the engine might stall even when you’re just idling, making it a troublesome experience especially when you’re at traffic lights or waiting in a queue.

Causes and Reasons:

• Erratic Timing Controls – Inconsistent timing due to a faulty CMP sensor can cause the engine to idle roughly.
• Signal Interruptions – Disrupted signal transmission between the CMP sensor and ECU can lead to misinterpreted data, affecting idling.

Diagnosis and Troubleshooting:

• Observe Idling Behavior – Take note if the car’s RPM fluctuates excessively or if there’s any shaking when the vehicle is stationary.
• OBD-II Scanner – It can provide codes indicating issues related to the CMP sensor affecting the idling.

DIY Repairs/Fixes:

• Clean the Sensor – Dirt or oil buildup on the sensor can affect its readings. Cleaning might restore its function temporarily.
• Sensor Replacement – If cleaning doesn’t help, consider replacing the faulty CMP sensor.

Repair/Replacement Costs:

• CMP Sensor Cleaning – A professional cleaning can range from $50 to $100.
• CMP Sensor Replacement – As discussed, a CMP sensor can be between $50 to $250. Labor ranges from $70 to $200.

Camshaft Position Sensor Bank 1, Symptoms #5: Reduced Power and Engine Light On

Often, issues with the camshaft position sensor can trigger your vehicle’s “Check Engine” light. Along with this, you might notice a clear reduction in engine power. This happens because the ECU may go into a ‘limp mode’ to prevent potential damage. The limp mode restricts the power output, ensuring the driver can only drive at lower speeds and revs, so it’s safer until the issue gets addressed.

Causes and Reasons:

• Protection Mechanism Activation – The ECU can activate ‘limp mode’ as a safety measure against perceived engine threats.
• Miscommunication with ECU – Faulty readings sent to the ECU can cause the activation of the Check Engine light.

Diagnosis and Troubleshooting:

• OBD-II Scanner – This tool is essential for interpreting Check Engine light codes and can quickly determine if the CMP sensor is the issue.
• Monitor Driving Experience – If the vehicle appears sluggish or lacks power, this may corroborate the CMP sensor fault.

DIY Repairs/Fixes:

• Reset the ECU – Disconnecting the battery for several minutes can reset the ECU and might temporarily solve the issue.
• Replace the Sensor – A lasting solution would be to replace the malfunctioning CMP sensor.

Repair/Replacement Costs:

• ECU Reset – Generally free, but always consult your vehicle’s manual before disconnecting the battery.
• CMP Sensor Replacement – Once again, the sensor can range from $50 to $250, with labor between $70 to $200.

Camshaft Position Sensor Bank 1, Symptoms #6: Difficulty in Starting

Besides the problem of the car cranking but not starting, a faulty CMP sensor can also cause delayed starting. You might find that the engine takes several attempts to start, or cranks longer than usual before it fires up. This is especially problematic during colder months when the engine requires precise timing for a successful cold start.

Causes and Reasons:

• Timing Discrepancies – Proper starting requires accurate timing. A faulty CMP sensor can disrupt this, causing starting issues.
• Delayed ECU Responses – Incorrect data from the CMP sensor can delay the ECU’s response, making the engine take longer to start.

Diagnosis and Troubleshooting:

• Cold Start Observations – Monitor how the car starts in cold conditions. Prolonged cranking can indicate a CMP issue.
• OBD-II Scanner – Error codes can point directly or indirectly to CMP-related starting issues.

DIY Repairs/Fixes:

• Check the Battery – Though not directly related, a strong battery ensures optimal starting. Ensuring its health can help eliminate other causes.
• Replace the Sensor – If identified as the problem, a sensor replacement can resolve starting difficulties.

Repair/Replacement Costs:

• Battery Test – Some auto stores offer free battery tests. However, a replacement battery can range from $50 to $200.
• CMP Sensor Replacement – The sensor itself costs between $50 to $250, and labor costs are typically $70 to $200.

Camshaft Position Sensor Bank 1, Symptoms #7: Erratic Transmission Behavior

A less obvious yet significant symptom of a bad CMP sensor relates to your vehicle’s transmission. The sensor plays a role in determining optimal shift points. If it sends inaccurate information to the ECU, it may cause erratic shifts, unexplained gear changes, or even make it hard for the transmission to decide which gear to engage in. This can result in a jerky ride, and in the long run, can also wear out your transmission sooner than usual.

Causes and Reasons:

• Incorrect Shift Points – The CMP sensor’s readings influence optimal shift points. Faulty readings can disrupt normal transmission behavior.
• ECU Confusion – Wrong data from the CMP sensor might confuse the ECU, leading to erratic gear decisions.

Diagnosis and Troubleshooting:

• Driving Assessment – Pay attention to unexpected gear shifts, especially during acceleration or cruising.
• OBD-II Scanner – Transmission error codes might hint at CMP sensor problems affecting the transmission.

DIY Repairs/Fixes:

• Transmission Fluid Check – Ensure your transmission fluid level is correct and in good condition. Sometimes, issues might not be sensor-related.
• Replace the Sensor – If the CMP sensor is the problem, replacement is the logical next step.

Repair/Replacement Costs:

• Transmission Fluid Check/Change – This service usually costs between $75 to $250.
• CMP Sensor Replacement – As discussed, the sensor is between $50 to $250, with labor costs ranging from $70 to $200.

Camshaft Position Sensor Bank 1, Symptoms #8: Backfiring and Popping

Inaccurate timing can also cause the engine to backfire or produce popping sounds. These are tell-tale signs of an ignition issue, which, in many cases, can be traced back to a failing camshaft position sensor. These sounds are often heard from the exhaust, signaling incomplete combustion in the cylinders.

Causes and Reasons:

• Ignition Timing Issues – Misreading from the CMP sensor can affect ignition timing, leading to backfires.
• Incomplete Combustion – Erratic data might cause incomplete combustion in the cylinders, resulting in popping sounds.

Diagnosis and Troubleshooting:

• Listen Closely – Popping sounds or backfires, especially during acceleration, are notable symptoms.
• OBD-II Scanner – Use this tool to identify any ignition or combustion-related error codes.

DIY Repairs/Fixes:

• Check the Exhaust System – Incomplete combustion can also be due to issues with the exhaust. Ensure it’s in good condition.
• Replace the Sensor – If the CMP sensor is found faulty, a replacement is essential.

Repair/Replacement Costs:

• Exhaust System Check – Inspections might cost between $50 to $150.
• CMP Sensor Replacement – The cost is between $50 to $250 for the sensor, plus labor costs of $70 to $200.

Camshaft Position Sensor Bank 1, Symptoms #9: Reduced Throttle Response

Lastly, an affected CMP sensor can negatively influence your vehicle’s throttle response. Ideally, when you press the accelerator pedal, the car should respond immediately. But if the sensor is malfunctioning, the vehicle may lag or show a delayed reaction to your throttle inputs. It can make overtaking or merging onto highways a challenging task, compromising both safety and driving pleasure.

Causes and Reasons:

• Disrupted Signal Flow – Faulty CMP sensor readings can delay or disrupt signal flow to the throttle.
• ECU Protective Measures – To prevent potential damage, the ECU might intentionally reduce throttle response based on erratic sensor data.

Diagnosis and Troubleshooting:

• Driving Evaluation – Monitor throttle responsiveness, especially during maneuvers like merging or overtaking.
• OBD-II Scanner – Error codes related to throttle or acceleration can indicate CMP sensor involvement.

DIY Repairs/Fixes:

• Check Throttle Body – Ensure the throttle body is clean and functioning properly, as issues here can also cause lag.
• Replace the Sensor – If the CMP sensor is determined as the root cause, replacement becomes necessary.

Repair/Replacement Costs:

• Throttle Body Cleaning – This can cost between $50 to $150 depending on the vehicle and location.
• CMP Sensor Replacement – The sensor price ranges from $50 to $250, with labor costs varying from $70 to $200.

Causes And Diagnosis

The most common trouble codes for CMP sensor issues include the P0016, P0017, and codes P0340 through P0349. For codes P0340 through P0347, the most likely causes are a faulty CMP sensor or damaged wiring. Meanwhile, the P0016, P0017, P0348, and P0349 codes likely mean your engine timing is off.

Note that a low engine oil or incorrect oil viscosity can also trigger these codes. Low engine oil or incorrect oil viscosity can affect the oil flow to the cam phasers (a part of the engine’s Variable Valve Timing system) and cause the camshaft to operate incorrectly.

Here are the steps that we recommend that you take to troubleshoot the problem:

1. Check The Engine Oil

Since a low engine oil can cause you trouble, we recommend checking the engine oil level first. It’s easy enough:

1. Perform the test while the engine is cool to get an accurate reading. Wait at least 15 minutes after driving.
2. Locate the engine oil dipstick in the engine bay, which usually has a yellow handle that says ‘Engine’.
3. Take out the dipstick, and then wipe the oil from the dipstick.
4. Reinsert the stick fully back into the slot.
5. Pull it out, and inspect the oil. There’s a minimum and maximum marker on the stick, and the engine oil needs to be somewhere in between the markers.

Most mechanics recommend that your engine oil should be at 3/4 between the minimum and maximum markers. If your engine oil is below the minimum marker, refill it, then reset the check engine light (such as how you’d reset a BMW check engine light). Afterward, drive for about 10 – 15 minutes and see if the check engine light and trouble code return.

You should also make sure that your last oil change was done properly with the correct oil viscosity. Putting in the wrong oil in your car can cause a low oil pressure, and this will affect lubrication on the camshaft. If the problem persists, let’s move on to the next step:

2. Scan For Trouble Codes

Always scan the OBD system with your OBD scan tool and see if there are any other codes present. Other codes that indicate a different issue in the car can be the source of your problem.

For example, even if you have enough oil, your car may have low engine oil pressure due to various reasons. Including a faulty oil pump, clogged oil filter, and incorrect oil viscosity. A low engine oil pressure will trigger the P0524 code. And if you see this—or any other trouble codes—you’ll need to rectify that as well.

3. Visually Inspect The Camshaft Position Sensor

If the trouble codes that you see are only CMP sensor-related, then it’s time to take a look at that sensor. Most cars will have the sensor accessible outside of the engine, so you don’t need to disassemble the engine. However, other engine components might get in the way.

In any case, once you locate and can gain access to the sensor, visually inspect it and the wiring. Look for any signs of physical damage to the sensor and the wiring. If the wires, connector, or the sensor itself has physical damage, this is likely the cause of your troubles.

If there’s no sign of damage, then it’s time to test the sensor itself:

4. Bench Test The Camshaft Position Sensor

To do this, you’ll need to disconnect the sensor from its electrical connector and unplug it from the engine. Don’t forget to disconnect the battery’s negative connection before you start working on the car.

Again, note that removing the sensor might require you to remove engine components to gain access, such as removing the air intake tube out of the way. Afterward, you’ll need a socket wrench to remove the sensor itself.

After you get the sensor out, inspect the connector for signs of damage or contaminants. This can cause the sensor to give false readings, but if there aren’t any, here’s how to bench test it with a multimeter:

1. Set the multimeter to the Ohm setting. Check your owner’s manual to find out the resistance range for the sensor in your specific car. For example, if it’s between 2,000 and 2,500 Ohms, then set the multimeter to the 20,000 Ohm setting.
2. Connect the leads to the sensor, and see if the multimeter is reading somewhere between the resistance specification. If it’s supposed to be 2,000 Ohms and you have a reading below that, then you have a bad sensor.
3. You should also test the connector in the engine. Set the multimeter to the continuity test setting, and then connect the negative (black) lead of the multimeter to the battery’s negative terminal.
4. Connect the positive (red) lead to the connector, and it should beep if it’s working normally.

The video above is a great visual guide on how to test the CMP sensor. You should also test the sensor for voltage by setting the multimeter on AC volts. Then clamp the leads to the sensor, and rotate a gear in front of the sensor. The reading should change if it’s working properly.

5. Inspect The Engine Timing

If everything seems to be working well so far, then you have good reason to suspect that your engine’s timing is off. Especially if you see the codes P0016, P0017, P0348, and P0349.

Unfortunately, checking the engine’s timing will require you to disassemble the timing belt/chain cover, and often the valve cover as well. This is not an easy job to do, so we recommend taking your car to a trusted auto repair shop instead for diagnosis.

However, there are some signs that you can look out for. If your car has a timing chain, bad engine timing will often produce a rattling noise when the engine is running. Meanwhile, a bad timing belt will usually produce a ticking noise instead.

Camshaft Position Sensor Bank 1 Repairs & Costs

Here are the repairs you need to do depending on your problem and the potential costs:

1. Low engine oil pressure. Around $100 for an oil filter replacement. But a faulty oil pump can set you back up to $1,000 to replace depending on the car’s make and model.
2. Camshaft sensor replacement cost is between $95 and $200 including labor.
3. Wiring repairs are usually $200 – $300 on average depending on the extent of the damage.
4. Timing belt/chain repairs depend on whether your car uses a belt or chain. Timing belts are usually around $500 including labor, while the timing chain can cost up to $800 due to the parts being more expensive.

Aside from replacing the oil filter and camshaft position sensor, we don’t recommend doing the job yourself. Replacing the oil pump and timing belt/chain isn’t easy since it requires quite a lot of disassembly. It’s best to leave these two jobs to professionals.

Wiring repairs are also difficult unless you have advanced knowledge and skills in electric engineering, in which case you probably don’t need our help anyway.

Camshaft Position Sensor Bank 1 Replacement

As for replacing an oil filter, you can learn more about how to do that in our guide. And if you have a faulty CMP sensor, here’s how you can replace it on your own:

1. Disconnect the car’s negative battery terminal.
2. Remove engine components that obstruct access to the sensor.
3. Disconnect the sensor’s electrical connector, and then remove it with a socket wrench. Gently remove the sensor once loose.
4. Inspect the sensor for signs of coolant or fuel leak (as indicated by a P0441 error code), the sensor should be drenched only in oil. If there are other fluids, you’ll need to fix the leak first.
5. Install the new camshaft position sensor and tighten it with a socket wrench. Check your service manual if the sensor needs to be torque-wrenched, but in any case, don’t overtighten it.
6. Reconnect the electrical connector.
7. Reinstall the engine components that you had to remove.
8. Clear the trouble codes to reset the check engine light. Drive the car for about 15 minutes, and if the check engine light doesn’t return, you’ve successfully replaced the sensor.

The video above from O’Reilly Auto Parts shows how to replace it in a 2005 Jeep Liberty. Aside from removing the air filter box (which you’ll know by learning how to change air filter in car), the process is pretty straightforward and you should be able to do it at home with basic hand tools. This can save you between $75 and $100 in labor costs.

Code P0016: Crankshaft and Camshaft Position Sensor Correlation

1. Code P0016 stands for Crankshaft Position – Camshaft Position Correlation (Bank 1 Sensor A).
2. The two common designs for camshaft position sensors (CMP) and crankshaft position sensors (CKP) are Hall Effect and permanent magnet.
3. The timing belt or timing chain holds the crankshaft and camshaft together to keep them synchronized, and the CKP and CMP sensors work together to keep the PCM informed about engine timing.
4. The common causes of code P0016 are a faulty cam or crank sensor, an open or shorted cam or crank circuit, an out-of-time timing belt/chain, a slipped/broken cam or crank tone ring, a problem in the VVT system, or a faulty PCM.
5. Due to the high number of possible causes, it is not possible to provide a repair cost estimate for code P0016 accurately.
6. Symptoms of code P0016 may include an engine that runs poorly, an engine that cranks but will not start, and an illuminated check engine light.
7. The most common solution to code P0016 is to replace/repair wiring, followed by replacing crankshaft/camshaft position sensors.
8. Code P0016 should be considered serious since the vehicle can be completely immobilized, and some types of engines can suffer serious, if not always fatal damage should the timing belt break or slip.
9. Ideally, a vehicle with this code should not be driven until the fault is found and repaired.
10. Repairing code P0016 should not present the average non-professional mechanic with undue difficulties, and it mainly involves testing circuits to verify that the resistance, continuity, ground integrity, and (where applicable), reference voltages comply with values specified by the manufacturer.

Frequently Asked Questions (FAQs)

Here are the frequently asked questions about CMP sensors and the answers you might find useful:

What Is A Camshaft

A camshaft is a rotating shaft that sits on top of the engine’s cylinders and has lobes (cams) that attach to it. Hence the name ‘camshaft’. The lobes rotate along with the shaft, and these lobes push the engine’s valves to open at the correct time. The intake valves allow fuel and air to enter the engine, while the exhaust valves allow exhaust gases to escape after the combustion process.

What Do Do After Replacing A Camshaft Sensor

After replacing a camshaft sensor, all you need to do is clear the trouble codes in the car’s On-Board Diagnostic (OBD) system to get rid of the check engine light (if there was one in the first place). Afterward, drive the car for about 15 minutes to verify that the issue is now resolved. If the check engine light returns, you’ll need to check the engine further.

How To Reset Camshaft Position Sensor

A camshaft position sensor cannot be reset. Once it’s faulty, you’ll need to replace it. The only reset you need to do is after you’ve replaced the sensor, which you can do with an OBD scan tool. If the check engine light persists after replacing the sensor, you likely have engine timing issues.

Where Is Camshaft Position Sensor A Bank 1 Located

Bank 1 refers to the row of cylinders (cylinder bank) that contains cylinder 1, which is the cylinder that sits farthest from the engine. If you have a V-configuration engine, this can either be the driver’s side or the passenger side bank, you’ll need to check your car’s service manual to find it as it differs depending on make and model. As for sensor A, the location also differs, but it’s usually the sensor on the opposite side of the car’s exhaust manifold.

What Does Camshaft Position Sensor A Bank 1 Circuit Malfunction Mean

Circuit malfunction means that the ECU is getting a voltage reading from the sensor outside of the accepted value. This usually indicates an electrical problem, which could be caused by a faulty sensor, bad electrical connectors, and/or wiring damage.

Camshaft Position Sensor Bank 1: Wrap Up

Let’s recap: the camshaft position sensor monitors the camshaft’s position and feeds that data to the ECU. This helps the ECU to control fuel injection, ignition timing, and other aspects of the engine to run smoothly.

If you have an inline-configuration engine, then there’s only one bank. But a V-configuration engine has two banks (two rows of engine cylinders). And bank 1 is where cylinder number 1 is located, and each bank has at least one camshaft position sensor.

Any camshaft position sensor issues will cause noticeable symptoms and can make driving uncomfortable. If you’re unlucky, it can also cause severe engine damage that might require a full engine rebuild. So, it’s best not to postpone repairs.