A crankshaft sensor tells your engine's computer where the crankshaft is at every moment

Your engine's crankshaft spins thousands of times per minute, and your car's computer needs to know its exact position to fire the spark plugs at the right when ready and inject fuel at the right time. A crankshaft sensor (also called a crank sensor) reads the position of the crankshaft and sends that information to the engine control module. Without this signal, your engine cannot start or run.

Advance Auto Parts stocks crankshaft sensors because they fail often enough that most car owners will need one at some point. A failed sensor typically causes a check engine light, rough idle, stalling, or a no-start condition. When a sensor fails, you need a replacement quickly — your car will not run reliably without one.

Key Takeaways

  • A crankshaft sensor reads the spinning crankshaft and sends position data to your engine computer so it can time spark plugs and fuel injection correctly.
  • Advance Auto Parts carries sensors for most vehicle makes and models, and you can search by your vehicle's year, make, and model on their website or in-store.
  • Crankshaft sensors typically cost between $50 and $250 depending on your vehicle, and installation usually takes one to three hours at a repair shop.
  • A failed sensor usually triggers a check engine light and may cause stalling, rough running, or a complete no-start condition.

How a crankshaft sensor works inside your engine

The sensor sits near the crankshaft or crankshaft pulley and reads a toothed ring or magnetic marker as the shaft rotates. As teeth pass the sensor, it generates an electrical signal that pulses in time with the crankshaft's rotation. Your engine computer reads these pulses and calculates the crankshaft's speed and position in real time.

The computer uses this information to determine the exact moment to fire each spark plug and the exact moment to open each fuel injector. If the sensor signal is weak, delayed, or missing, the computer cannot make these calculations, and the engine will not run correctly. Some vehicles have two crankshaft sensors — one for speed and one for position — so you may need to replace both if both have failed.

Finding the right sensor at Advance Auto Parts

Advance Auto Parts carries crankshaft sensors for most domestic and imported vehicles. To find the correct sensor for your car, you will need your vehicle's year, make, model, and engine size. You can search on the Advance Auto website by entering this information, or you can visit a store and ask a staff member to look it up in their system.

The sensor you need depends on your specific engine — two vehicles of the same year and model may have different engines and therefore different sensors. Ordering the wrong sensor wastes time and money. If you are unsure which sensor your vehicle uses, bring your vehicle identification number (VIN) to the store, and staff can confirm the correct part.

Sensor cost and installation time

Crankshaft sensors at Advance Auto Parts typically range from $50 to $250, depending on your vehicle's make, model, and year. Domestic vehicles and common imports tend to be on the lower end of that range, while luxury vehicles and some imports cost more. Advance Auto also carries sensors under different brand names — OEM (original equipment manufacturer) sensors usually cost more than aftermarket alternatives, but both types are stocked.

Installation at a repair shop usually takes one to three hours. The sensor location varies by vehicle — some are straightforward to reach and take 30 minutes, while others require removing the engine cover, timing belt cover, or other components. Labor costs at a shop typically run $100 to $300 depending on your location and the shop's hourly rate. If you have mechanical experience, you can install the sensor yourself and save the labor cost, but this is not a beginner job on most vehicles.

Signs your crankshaft sensor is failing

A failing crankshaft sensor usually triggers a check engine light on your dashboard. The light appears because the engine computer detects that the sensor signal is missing, weak, or inconsistent. You can have the code read for free at many Advance Auto locations using their code reader service, which will confirm whether the sensor is the problem.

Before the check engine light appears, you may notice your engine running rough at idle, hesitating when you accelerate, or stalling at stop lights. In some cases, the engine will not start at all. These symptoms can also be caused by other problems — a bad alternator, a failing ignition coil, or a fuel pump issue — so reading the diagnostic code is the only way to know for certain.

Choosing between OEM and aftermarket sensors

OEM sensors are made by your vehicle's manufacturer or an authorized supplier and carry the manufacturer's warranty. Aftermarket sensors are made by third-party companies like Bosch, Standard Motor Products, or Dorman and are usually cheaper. Both types are available at Advance Auto, and both will work in your vehicle.

The main trade-off is price versus warranty length. An OEM sensor may cost $50 to $100 more but often comes with a longer warranty — sometimes the full manufacturer warranty on your vehicle. An aftermarket sensor costs less upfront but may have a shorter warranty, typically one to three years. If your vehicle is still under manufacturer warranty, using an OEM sensor may protect your warranty coverage for other parts, though this varies by manufacturer.

What to do if you cannot find your sensor at Advance Auto

If Advance Auto does not have your sensor in stock, you can order it online for in-store pickup or home delivery. Most orders arrive within one to three business days. You can also call your local Advance Auto store and ask them to check their system for availability at nearby locations.

If your vehicle is very old, very new, or unusual, the sensor may not be in Advance Auto's system. In that case, a local repair shop or your vehicle's dealership can order the correct sensor. A dealership will charge more but can may provide the part is correct for your vehicle. A local independent shop can often order the same part at a lower cost if you bring them the part number from your vehicle's service manual or a previous repair receipt.

Frequently Asked Questions

Can I drive with a check engine light from a bad crankshaft sensor?

You can drive short distances, but the engine may stall, hesitate, or refuse to start at any moment. The longer you drive, the more likely the engine will fail completely. It is safer to have the sensor replaced before driving long distances or in heavy traffic.

How long does a crankshaft sensor last?

Most crankshaft sensors last 80,000 to 150,000 miles, though some fail earlier due to heat, moisture, or vibration. There is no set maintenance schedule for replacing them — you replace them only when they fail. Some vehicles may never need one, while others may need two or three over their lifetime.

Is a crankshaft sensor the same as a camshaft sensor?

No. A crankshaft sensor reads the crankshaft, and a camshaft sensor reads the camshaft. They are different parts in different locations and are not interchangeable. Your vehicle may have both, and either one can fail independently.

Can I install a crankshaft sensor myself?

Yes, if you have mechanical experience and the right tools. The difficulty depends on your vehicle — some sensors are accessible in 30 minutes, while others require removing covers or other components. If you are unsure, a repair shop can do it faster and with a warranty on the work.

What if I replace the sensor and the check engine light stays on?

The light may stay on until you clear the old code from the computer. A repair shop or Advance Auto can clear the code for you after the sensor is installed. If the light returns after clearing, a different problem may be causing the same symptoms, and you should have the code read again.