The internal combustion engine contains a device called the camshaft. The job of the camshaft is to manage the intake of gasoline and the emission of fumes from the exhaust system.
There are offset lobes attached to the camshaft which control the exhaust valves and intake valves. A timing belt or chain link the camshaft to the crankshaft, which is how the camshaft gets its drive.
The engine control unit of the vehicle monitors the camshaft’s rotating position with a component called the “camshaft position sensor.” Based on the information which the sensor transmits, the engine control unit will determine how much fuel should get injected into the combustion chamber and the timing of the spark.
Top 5 Bad Camshaft Position Sensor Symptoms
There are a lot of things that can go wrong in your vehicle if you have a bad camshaft position sensor. You will know when these problems present themselves because the symptoms will become very apparent.
Below are five common signs which will indicate a faulty camshaft position sensor.
1) Ignition Issues
The mixture of air and fuel in the internal combustion engine requires a spark in order for the ignition to take place. In certain vehicles, the spark cannot be generated if there is a bad or faulty camshaft position sensor.
If you cannot generate a spark, then you cannot start your engine. You might not immediately assume the camshaft position sensor is to blame for an engine that won’t start. But if you take your vehicle to a repair shop, do not be surprised if the mechanic tells you that the camshaft position sensor is to blame.
2) Difficulty Shifting
If you are driving an automatic transmission vehicle and your camshaft position sensor goes bad, you can expect your set gear to lock in place. This means that you will have trouble shifting to another gear, although you might not be able to shift at all.
The only thing that you’ll be able to do is to turn off your car, wait a few seconds, and then turn it on again. This is just a temporary solution so that you can get your vehicle to the nearest mechanic quickly.
If you don’t replace your camshaft position sensor, the shifting problem will come back for sure.
3) Poor Engine Performance
A faulty camshaft position sensor will cause an improper amount of fuel to be injected into the cylinder chamber. The engine will not respond very well to this because it depends on a proper mixture of air and fuel to function adequately.
When you step on the gas pedal to accelerate, you will notice weaker performance. You won’t be able to go faster than 30 to 40 miles per hour in many cases. Not only will you fail to go faster, the vehicle may start to stutter and jerk around as well.
4) Low Fuel Efficiency
The fuel injectors will possibly be putting too much fuel into your cylinder chamber if you have a bad camshaft position sensor. As more fuel gets used up, this will create a problem for the fuel efficiency of your vehicle.
You will notice that your gas mileage is reduced and that you’ll be pumping gas more frequently.
5) Check Engine Warning Light
The camshaft position sensor is a component inside the engine. If this sensor were to malfunction or go bad, it will cause a chain reaction that will affect other functions of the engine.
It should be no surprise that the “Check Engine” warning light will illuminate on the dashboard if this happens.
Of course, this light could illuminate due to any number of problems inside the engine besides a bad camshaft position sensor. But if you experience at least a few of the other symptoms that were mentioned above, then you can assume there is a problem with the camshaft position sensor.
Camshaft Position Sensor Replacement Cost
We recommend Parts Geek for the best prices and selection.
Out of all the sensors in your vehicle, a camshaft position sensor is often one of the least expensive. Depending on your make and model, expect to pay between $20 to $100 in most cases for a replacement sensor.
On top of that, add about $60 to $90 in labor costs. Altogether, you’re looking at a total between $80 and $190 (+ tax) to replace your camshaft position sensor. If you’re having the replacement performed at a dealership or you drive certain luxury or performance vehicles, plan on spending more.
Fortunately, those with even a bit of mechanical experience can often replace the sensor on their own with the help of a repair manual or YouTube video specific to your vehicle. In many cases the location of the sensor is easy to get to but in others, it can be a real pain.
- 6 Signs of a Bad Fuel Pump Relay (And Replacement Cost) - January 28, 2025
- 12 Common Mistakes to Avoid When Bleeding Your Brakes - January 22, 2025
- 7 Reasons Your Heated Seats Stopped Working (And Repair Costs) - January 8, 2025
I have a 2004 hyundai xg350 i changed the camshaft sensor but now it starts and dies what is wrong with it?
No idea. Is it throwing any codes? Could the timing be off? How’s the air fuel mixture? An OBD scan tool should help you narrow it down a bit more.
Hi I have Chevrolet aveo 2005 model and it start sometime,when I check the camshaft & crankshaft sensors are filled with oil,so m not sure if they are the cause of no start problem
I have a 2017 Ford Flex its been running sluggish at times it seems like it has to jerk into the next gear a couple days ago it shut off on me I was able to get it to my dads driveway before it completely shut off on me. I could get it to start but when I put it in gear it would shut off. My dad had his mechanic hook his computer to it it read 2 Cam sensors A-B, Crankshaft code, o2 sensor.. He seems to think its the timing chain it somehow got stretched the car just hit 100000 miles last week I get my oil changed every 3000 miles. Could it really be the timing or maybe just the position sensors are bad?
I really don’t know, I’m not even sure if all those codes are related. Do you hear any chain rattle on startup or during operation? I’m wondering if perhaps one of the timing chain tensioners is loose or has failed?
You might want to check the forums for the Ford Flex, see if those codes all being thrown simultaneously is a common issue with a known root cause. Otherwise, I think you’ll have to bring it into a shop to have the problem diagnosed.
My Chevrolet Beat LT Petrol, 2010 model has LOW MILEAGE issue. Engine is ok. Sometimes doesn’t start or take 3-4 long selfs to be started. But when I push the CAMSHAFT SENSOR, then it starts the engine at a SINGLE SELF.
Check the connection at the camshaft sensor. Sounds like a bad ground or connection.
How cam I test to see if my camshaft sensor is really the problem? Fuel pump is good, fuel injectors, fuel rail, fuel filter as well as fuses. But 1994 Honda Accord Dx 2.2L still won’t start. Fuel related. How can i verify that this is the issue?
In the factory service manual they should have a specification for expected voltages on each of the camshaft sensor pins. They may even describe a testing procedure.
Can a bad camshaft cause oil to leak out?
Oil leakage from the camshaft is likely caused by a bad camshaft seal and not the camshaft itself. Some camshaft position sensors have seals as well that may leak over time.