The camshaft position sensor is one of those parts that very few drivers know about but that still has quite an important role in the overall functioning of your engine. It is a small electrical sensor that keeps track of the position of your camshaft in relation to the crankshaft to maximize the timing and precision of your engine.
If your camshaft and your crankshaft are not aligned properly then your engine timing will be thrown off drastically. And while older models of vehicles were not equipped with a camshaft position sensor, they are included in newer models because they are much more efficient at maintaining this precise timing which means you're going to have better engine performance, better fuel economy, and fewer trips to the mechanic as a result.
When your engine timing becomes misaligned, you're going to suffer things like engine misfires and potentially even a catastrophic engine failure if your timing gets so bad that your pistons end up crashing into your valves, for instance. This is the kind of thing that will happen when your timing belt fails on you.
The camshaft position sensor is in place to relay data about where your camshaft is in relation to everything else so that your car's computer can make subtle alterations to the timing of any other parts as necessary so that everything is working in the correct order. If your camshaft position sensor starts to fail, then it's much easier for all the rest of your engine to fall out of order as well. For that reason, you want to make sure it's operating as well as it can and keep your eyes open for any problems that indicate it may be broken, dirty, or failing.
What Are the Signs of a Bad Camshaft Position Sensor?
When your camshaft position sensor starts to go bad on you there are a few symptoms that you can be aware of to let you know that this is the particular issue you're having.
Engine Stalls: When the camshaft position sensor isn't working the way it should be you may experience your engine shutting down on you while you're driving. If it sends the wrong signal to your computer, the fuel injectors may stop injecting fuel at the right time which will prevent combustion from occurring when you need it to and that can make your engine stall out as a result. As you can imagine, this could be extremely problematic if it occurred while you're driving down the highway. This is one of the major reasons why keeping your camshaft position sensor in good working order is so important.
Jerking and Surging: Even if your engine doesn't fail and stall out, you may end up losing power because the timing is so thrown off by a bad camshaft position sensor. This can cause your vehicle to surge and jerk in unexpected ways. This happens because the PCM in your vehicle, the powertrain control module, is getting incorrect signals from your camshaft position sensor.
Ignition Problems: You could just as easily have problems even getting your vehicle started when you have a problem with your camshaft position sensor. This is because your PCM will not be sending the correct information to your spark plugs which means the ignition process will not be able to initialize and your car won't even get started when you attempt to do so.
Problems Accelerating: Any time you try to accelerate your vehicle you're putting greater demand on the engine, and that means you're going to be burning more fuel to meet those demands. When your camshaft position sensor is not sending the correct signals, your fuel injectors are not going to be adding the correct amount of fuel to the combustion chamber and you're not going to be able to meet the demands you're trying to put on your engine when you're accelerating. If this situation is bad enough you'll be operating in what is known as limp mode, and your vehicle will be underperforming until such time as you can get to a mechanic to try to get it fixed.
Problems Shifting: Although this may not happen in every vehicle, in some models when you have a problem with your camshaft position sensor you may have some problems with your transmission locking up on you. When this happens, you can find yourself stuck in one specific gear until such time as the problem is resolved. Depending on the nature of the problem, simply pulling over and letting your car rest could possibly fix this issue until such time as you're able to shift gears again, but it will pop up again later until you end up getting the sensor fixed.
Bad Gas Mileage: It should come as no surprise that you're going to suffer some issues with your fuel economy if your camshaft position sensor isn't working since it's directly related to how fuel is injected into the cylinders. When it starts sending faulty signals, you'll end up wasting fuel that isn't being burned at the correct time or even burn it all. This is going to mean you have a poor performance overall, but you'll still be heading to the gas pumps more often.
Check Engine Light: When the check engine light pops up on your dashboard it could signify any one of literally hundreds of problems, but if it does happen in conjunction with some of the other symptoms we've mentioned then that should indicate you need to check out the camshaft position sensor to see if that's the source of the issue.
Getting to the root of a check engine light is a difficult proposition because there are so many potential causes for it. The best you can do is either get your vehicle to a mechanic to have it properly diagnosed or make sure you pick up an OBD2 scanner of your own to plug into your car and find out why your check engine light came on in the first place. This type of scanner is what a mechanic will use to diagnose the problem as well, and you can get your own from a site like amazon.com for as little as $30 to $40. If you have an interest in diagnosing automotive issues and doing DIY car repairs, this could be an invaluable tool to have in your home garage.
Can I Drive with a Bad Camshaft Position Sensor?
Technically you can drive with a bad camshaft position sensor, at least for a while. As we said, older vehicles didn't even have camshaft position sensors as part of the engine, and they were able to run just fine. And when your camshaft position sensor goes bad, you will likely still be able to drive your car for an extended amount of time. The problems are as we mentioned above in the signs and symptoms of a badge camshaft position sensor. These things are going to continue to happen as a result to the point that it could cause some serious damage to your engine overall.
It's not exactly fair to compare a modern car with a camshaft position sensor to an older vehicle that did not have one at all because the engines were designed differently. Since those older engines were never meant to have camshaft position sensors in them, not having one doesn't affect their performance in any way. But because your vehicle was designed to rely on the information that comes from a camshaft position sensor, where the sensor fails it will have a much greater impact on how the vehicle performs as a result.
How Much Does It Cost to Replace a Camshaft Position Sensor?
A camshaft position sensor is going to cost you somewhere between $125 and $200 to get repaired if you head to a mechanic to get the job done. A good portion of the cost is going to be labour as the camshaft position sensor itself is not usually all that expensive. There is a wide range that will depend on the make and model of your car, but some camshaft position sensors could start as cheap as $20 from auto supply stores.
There are some rare models of vehicles that have camshaft position sensors located in much harder to reach places than others. In these vehicles, getting to the camshaft position sensor is a much more labor-intensive job and that can end up pushing the cost of the repair quite a bit higher as a result. Again, this is rare and most vehicles won't have this issue.
What Causes a Camshaft Position Sensor to Fail?
There are a number of potential causes for a camshaft position sensor to go bad on you. Technically a camshaft position sensor could last the life of your vehicle, but a handful of unexpected things could occur that cause it to work improperly as well.
- Mechanical damage could be at the root of your sensor not working properly if your car has been in an accident at some point in time, or some other kind of incident directly causes damage to the sensor itself.
- Your camshaft position sensor also may be suffering from a short circuit somewhere along the line as well.
- If there's been an interruption in the connection between your camshaft position sensor and your control unit, such as a faulty wire or broken wire that could cause issues with the sensor
- A dirty sensor is also a potential problem as well if too much grease, debris, or other buildup has gummed up the sensor so that it can no longer relay accurate data to your car's computer.
Can You Clean a Camshaft Position Sensor?
The camshaft position sensor is one of those items that may actually be able to function again after a good cleaning rather than simply replacing it. This could definitely save you some money in the long run as long as you get the job done properly and you're careful about how you're doing it.
Step 1: Start by disconnecting the negative cable from your battery. This is always a good idea before dealing with any electronics under the hood of your car. The negative cable is the black one, and all you need to do is disconnect it from the terminal.
Step 2: Refer to your owner's manual to determine the precise location of your camshaft position sensor. It can vary from one model of vehicle to another, so don't expect it to be in the same place you may have discovered one last time. Once you find it, you'll notice it's connected to your ECU by three wires. Disconnect them and keep them separate so you know how to connect them correctly again when you replace the sensor.
Step 3: Unscrew the sensor from the distributor. You may need to use a little elbow grease to get it free, including gently prying it out of place with the edge of your screwdriver. Don't try to force it too hard, however.
Step 4: Using a clean rag you can wipe the sensor clean; you may need a little bit of a cleaning solution or solvent to get it cleaned up here at this point. Just a squirt of something like WD-40 and then wipe it clean with a lint-free rag.
Step 5: You can replace the camshaft sensor now, tighten the screws back in place and reattach the wires where they are supposed to be connected. With any luck it should be working properly again and not giving you any problems.
The Bottom Line
Your camshaft position sensor is a small item, and many drivers may feel it's not particularly significant, especially considering the amount of time in automotive history that cars existed without these sensors even being included. However, since they are part of how modern vehicles operate their function really is important to ensuring your engine is working the best way it possibly can. When the sensor isn't working properly, the risk to your engine not working properly increases drastically. For that reason, you want to keep your eyes open for any problems that may be occurring with your camshaft position sensor and get it fixed as soon as possible whenever you notice something going wrong.