What a camshaft position sensor does and why it matters

Your camshaft position sensor tells your engine's computer exactly where the camshaft is at any given moment. The camshaft controls when your engine's intake and exhaust valves open and close — timing that has to be precise to within a fraction of a second. Without accurate position data, your engine can't fire the spark plugs at the right when ready, and fuel injection goes out of sync.

When this sensor fails, your engine typically won't run at all, or it will run so poorly that the check engine light comes on and your car goes into a reduced-power mode. You'll notice rough idling, stalling, hard starting, or a complete no-start condition. Some cars will limp along at low power; others won't start.

The sensor itself is a small electronic device, usually mounted on or near the cylinder head where it can read a tone ring or reluctor wheel on the camshaft. It costs between $150 and $400 for the part itself, depending on your vehicle make and model. Labor to replace it typically runs $100 to $300, though some vehicles require removing other components to reach it, which can push labor time higher.

Key Takeaways

  • A camshaft position sensor failure usually triggers the check engine light and causes rough running, stalling, or a no-start condition.
  • The sensor itself costs $150 to $400, and labor to replace it runs $100 to $300, though some vehicles require more extensive disassembly.
  • You can have the fault code read for free or low cost at many auto parts stores, which will confirm whether the sensor is the problem.
  • Replacement is a straightforward job on many vehicles but requires the right tools and knowledge of your specific engine layout.
  • Driving with a failed sensor is not safe — your engine may stall without warning, and you risk damage to the catalytic converter if you ignore the problem.

How to know if your camshaft position sensor has failed

The most reliable way to confirm a sensor failure is to have the fault code read from your engine computer. Most auto parts stores (AutoZone, O'Reilly, NAPA, Advance Auto Parts) will read the code for free. You're looking for codes in the P0010 to P0019 range — these specifically point to camshaft position sensor problems. Code P0010 means "Camshaft Position Actuator Circuit Bank 1," P0014 means "Camshaft Position Actuator Circuit Bank 2," and similar variations exist depending on which sensor failed and which bank of the engine it monitors.

Symptoms alone aren't enough to diagnose a sensor failure, because rough running and stalling can come from spark plugs, fuel injectors, timing chain problems, or other causes. The fault code narrows it down. If you get a P0010 or P0014 code, the sensor is almost certainly the culprit — these codes are specific enough that other problems rarely trigger them.

Some vehicles have two camshaft position sensors (one for intake, one for exhaust), and occasionally only one fails. The code will tell you which one. If you're having the work done at a shop, they should test both sensors before replacing either one, because replacing the wrong sensor wastes money and time.

What happens during replacement

On most vehicles, the sensor is held in place by one or two bolts and has an electrical connector that unplugs. The technician disconnects the wiring, removes the bolts, and slides the old sensor out. The new sensor goes in the same way — bolt it down, plug in the connector, and clear the fault code from the computer.

On some engines, the sensor sits in a tight spot behind other components. You might need to remove the valve cover, timing cover, or intake manifold to reach it. This is where labor time can jump from 0.5 hours to 2 or 3 hours. A Honda Civic sensor might take 30 minutes; a Subaru or some Ford models might take 2 hours because of the layout.

After replacement, the technician will clear the fault code and test-drive the vehicle to confirm the engine runs smoothly and the light doesn't come back on. Some shops will also verify that the new sensor is reading correctly using a scan tool.

Doing the work yourself versus taking it to a shop

If you have basic mechanical skills and the right tools, you can replace a camshaft position sensor yourself on many vehicles. You'll need a socket set, possibly a wrench, a screwdriver, and a scan tool to clear the fault code afterward. Some auto parts stores will clear the code for free once you've installed the new sensor; others charge $20 to $50.

The main risk is getting the sensor location wrong or damaging the connector or wiring during removal. If you're not confident, a shop is the safer choice. The labor cost is usually worth avoiding a mistake that could cost more to fix.

If you do the work yourself, buy the sensor from a reputable supplier — OEM (original equipment manufacturer) parts are more reliable than the cheapest aftermarket options, though they cost more. A failed replacement sensor is frustrating and expensive to diagnose and fix again.

What the repair costs break down to

A typical camshaft position sensor replacement at an independent shop runs $250 to $700 total. At a dealership, expect $400 to $1,000 or more, because dealerships charge higher labor rates and use OEM parts exclusively. The difference is usually in labor rate and parts markup, not in the complexity of the job itself.

Some shops will charge a diagnostic fee ($50 to $150) to read the code and confirm the sensor is the problem. If you have the code read for free at an auto parts store first, you can bring that information to the shop and skip the diagnostic fee.

If both camshaft position sensors need replacement (which is rare but happens), double the parts cost and add a bit to labor, though not double — the second sensor usually takes less time because the technician is already familiar with the location and has the area open.

Why you shouldn't ignore this problem

A failed camshaft position sensor is not a slow leak or a worn belt — it's a critical failure that affects whether your engine runs at all. Driving with a confirmed sensor fault is risky. Your engine may stall without warning, leaving you stranded in traffic or on a highway. If you ignore the problem and keep driving, you risk damaging the catalytic converter, which is far more expensive to replace ($800 to $2,500).

Some vehicles will go into limp mode and run at reduced power, which might let you drive to a shop slowly. Others won't start at all. Either way, the repair needs to happen soon — not because of urgency pricing, but because the vehicle isn't safe to drive in its current state.

Aftermarket versus OEM sensors

OEM sensors (made by the vehicle manufacturer or their approved supplier) cost more but have a track record specific to your vehicle. Aftermarket sensors from brands like Bosch, Standard Motor Products, or Delphi are cheaper and often work fine, but quality varies. Some aftermarket sensors fail within a year; others last as long as OEM parts.

If you're having the work done at a shop, ask whether they warranty the part. Many independent shops offer a 12-month or 24-month warranty on parts they install, which protects you if the sensor fails again soon. Dealerships typically warranty OEM parts for longer. If you're buying the part yourself and installing it, you're responsible for any failure.

A middle-ground option is a remanufactured sensor — a used sensor that has been cleaned, tested, and rebuilt to factory specs. These cost less than new OEM but more than cheap aftermarket, and they often come with a warranty.

Frequently Asked Questions

Can I drive with a bad camshaft position sensor?

Not safely. Your engine may stall without warning, and you risk catalytic converter damage if you ignore it. Some vehicles go into limp mode and run at reduced power, which might let you drive slowly to a repair shop, but this is not a long-term solution. Have the sensor replaced as soon as you can.

How long does a camshaft position sensor last?

Most sensors last 100,000 to 150,000 miles or longer, though some fail earlier due to heat, moisture, or manufacturing defects. There's no maintenance schedule for replacing them — they're replaced only when they fail. If your vehicle has high mileage and the sensor is original, failure is more likely.

Will the check engine light go away after I replace the sensor?

Yes, once the new sensor is installed and the fault code is cleared from the computer. If the light comes back on within a few days, the new sensor may be defective, or there may be a wiring problem. Have the code read again to confirm.

Do I need to replace both camshaft position sensors at the same time?

Only if both are failing. Have the code read to see which sensor triggered the fault. If only one code appears, only one sensor needs replacement. Replacing both when only one is bad wastes money. However, if your vehicle is very old or high-mileage, your technician might recommend replacing both as preventive maintenance.

What's the difference between a camshaft position sensor and a crankshaft position sensor?

The crankshaft position sensor monitors the crankshaft (which spins the wheels), while the camshaft position sensor monitors the camshaft (which controls valve timing). Both are critical, but they monitor different parts of the engine. A failed crankshaft sensor usually causes a no-start; a failed camshaft sensor causes rough running or no-start depending on the vehicle.