The camshaft position sensor in your engine is also known as a CMP. It's an electrical component that helps maintain the proper functioning of your car's engine. Every modern car has one, though older vehicles were made without them. It can cause some serious problems if your camshaft position sensor starts to fail on you, so it's a good idea to know exactly what it does, where to find it in your vehicle, and what to do about it when something starts to go wrong.
What is a Camshaft Position Sensor?
As the name suggests, the entire purpose of a camshaft position sensor is to keep track of the position of the camshaft in your vehicle. The camshaft position sensor tracks the location of the camshaft in relation to the crankshaft. These two parts mean to work and exact synchronization to ensure proper functioning of your engine. If one or the other is misaligned, then you're going to suffer a lot of damage like engine misfires, idling problems, and potentially some catastrophic engine failure. For that reason, there are many components that need to keep your car's engine precisely aligned. In fact, there's also a crankshaft position sensor in your engine which does A similar job but for the crankshaft instead of the camshaft.
The camshaft position sensor can be a little hard to find in your engine because there's no standard location for it. It really depends on the make, model, and year of your vehicle. Many times, it's located in the back of the cylinder head or somewhere next to the engine block, but there are no guarantees. You'll have to look up the specs for your individual vehicle to determine for sure where it is.
Signs of a Bad Camshaft Position Sensor
If there is something wrong with your camshaft position sensor there are a few signs you can be on the lookout for to let you know that this is the issue.as with many problems in a car's engine, there could be other root causes for a lot of these symptoms. With that in mind, if you experience a couple of these at the same time that can help you narrow down the cause to potentially being a problem with your camshaft position sensor. If nothing else, it will give you and your mechanic a place to start looking when things go wrong.
Check Engine Light
This is often the first symptom of many different problems that can happen under the hood of your car. It's both helpful in letting you know something is wrong, but rather unhelpful in how nonspecific it is in terms of telling you exactly what the problem is. A check engine light can literally mean hundreds of different things have gone wrong with your vehicle
If you want to narrow it down to the root cause, you're going to need something called an on-board diagnostic scanner to figure it out. Often called an OBD2 scanner, these are the tools that a mechanic will use whenever a warning light shows up on your dashboard to figure out exactly what's going on. You plug this into your car, and it will give you a specific code with a direction to a more specific area but what's going on.
While mechanics always have an OBD2 scanner on hand many drivers do not have these. However, if you are interested in doing any kind of do it yourself car repair it could be in your best interest to invest in one of these to have in your home garage. You can buy them on Amazon.com and there are some models that are exceptionally affordable. You may be able to get a reliable OBD2 scanner for as little as $30 or so. There are other models that are much more expensive if you want to invest in a more complicated one, but for basic car diagnostic purposes, one of the cheap scanners should be able to get the job done for you pretty well.
It's tempting for many drivers to ignore a check engine light when it pops up on your display because, as we said, there are literally hundreds of reasons for this to show up and in many cases it seems like you can safely drive your car for weeks, months, or maybe even years with that light illuminated. Unfortunately, you run the risk of some kind of traffic failure if it's a serious problem that you don't get addressed as soon as you can. It's not worth the risk of thousands of dollars in repairs.
Jerking or Surging
When your car is in motion and the camshaft position sensor starts to fail on you it's possible that the engine will simply lose power. That can cause the vehicle to lurch or surge unexpectedly. The reason this happens is because your powertrain control module, or PCM, isn't getting the correct signals from the camshaft position sensor anymore. Your PCM controls the fuel injector and the ignition system control, so it will not be relating the correct signals and potentially result in the fuel injected incorrectly into the cylinders causing the engine to misfire.
It's possible that your car can shut down or stall while you're driving if the camshaft position sensor is failing. when the wrong kind of faulty signal is sent from your position sensor to the PCM, the fuel injectors may stop delivering fuel entirely to the combustion chamber of your vehicle. That will stop your engine from working entirely, and it will stall out on you. That would be extremely bad news if it happened while you're in the driveway, but if it happens while you're driving down the road, or worse when you're driving at a high rate of speed on a highway, this could be catastrophic and dangerous for you. That's why getting the sensor checked out the moment you realize something is wrong is of vital importance.
If your camshaft position sensor is not sending the proper signals to your PCM, you will potentially end up having issues starting the vehicle. Your spark plugs will not create the spark to start the ignition process because the computer controlling your vehicle won't realize you're even trying to start the car at that point.
This may not affect every vehicle equally, but there are some models that will cause your transmission to lock up when there's a problem with your camshaft position sensor. That could keep you in a first gear until such time as you get the problem with the sensor addressed. Sometimes letting the car rest for a bit will clear up this problem and you'll be able to shift gears again, but it will keep occurring unpredictably until the root problem with the camshaft position sensor is fixed.
Much like issues with the car surging unexpectedly, you could have problems accelerating when the camshaft position sensor isn't working the way it should. Because the signal isn't telling your car's computer that you need to have fuel injected at the right time, you're not going to be able to burn that fuel to maintain the power that your engine is supposed to be out putting on a regular basis. That in turn means you'll end up operating the vehicle as though it were in limp mode. When this happens it's unlikely you'll be able to get anywhere near the speed that you're used to, and sometimes you won't even be able to maintain the rate of speed of traffic around you which will require you to pull off the road for your own safety and the safety of other drivers.
Poor Gas Mileage
As we've mentioned with some of these other issues, a big problem when the camshaft position sensor isn't working right is that it's not giving the correct signals on when the fuel needs to be injected into the cylinder in your engine. The result of that is you'll end up wasting fuel inefficiently rather than burning at the way your car is supposed to. When that happens, you'll find yourself heading to the pumps a lot more often than normal to refill the tank.
Camshaft Position Sensor Repair Cost
A camshaft position sensor is not a particularly expensive item to get replaced in your vehicle, so you don't need to worry about a hugely expensive bill, and something goes wrong. You might end up paying anywhere between $125 and $200 to get this done by a mechanic.
If you want to try your hand at replacing it yourself, you can pick up a new camshaft position sensor at AutoZone. They run anywhere from about $20 to as much as $300.The price variation depends on the make, model, and year of your vehicle more than anything. The labour costs will vary greatly depending on the mechanic you choose to go with him where it is exactly in the country that you live.
Some more rare vehicles may have camshaft position sensors that are harder to get to under the hood, which may require a little bit more intense work for mechanics. As well, the part is going to cost you quite a bit more money for a vehicle that is less common on the roads. That's why some of them can get up to $300 or more.
Can I Replace My Own Camshaft Position Sensor?
If you want to save yourself some money you can definitely replace the camshaft position sensor on your own. In terms of complexity, we would rank this as a beginner level repair job in one that shouldn't be too difficult at all if you are comfortable working under the hood of your car. If you can change the oil filter in your car, you can absolutely change the camshaft position sensor.
If you've never attempted that job before and aren't sure what to do, there are some handy guides that you can look at on the internet that can walk you through the process step-by-step. Even more convenient are videos that you can look up on YouTube that show you what needs to be done. These are particularly handy because there are many YouTube channels that are run by professional mechanics who have decades of experience in auto repair. You can benefit from all that experience by seeing exactly what they're doing, which is almost as good as some hands-on education or from a mechanic. And because it's a video, if there's anything you're unsure of you can just easily scroll back and watch it over again to see what needs to be done.
The definite bonus to getting it done yourself is sad, if you are camshaft position sensor only costs $20 or so, you're saving quite a bit of money on labour charges to handle it on your own.
The Bottom Line
Even though most drivers aren't even aware of what a camshaft position sensor is, it clearly does a very important job inside your engine. When the camshaft position sensor isn’t functioning properly, your entire engine is in jeopardy and the overall performance of your vehicle will suffer greatly as a result. The fact that it's such a small piece of technology and so easy to swap out and repair is definitely an upside for when something does go wrong.
Technically speaking the camshaft position sensor is meant to last the entire lifetime of your vehicle. It doesn't experience the same kind of wear and tear that something like a serpentine belt or brake pads will by any means. That said, parts do tend to wear out after a long enough period of time regardless of how long they were meant to last so there's always a chance that something could go wrong with yours and you'll need to get it fixed.
Just keep an eye out for the symptoms we've mentioned, and if you experience more than one, definitely take your car to mechanic to get it looked at or invest in an OBD2 scanner to diagnose the problem on your own and find out if the camshaft position sensor is the problem that you're dealing with. Getting this fixed as soon as you can ensure a smooth running vehicle that's safer and cheaper for you in the long run.