Skip the auto shop - Our mechanics make house calls

Symptoms of a Bad or Failing Crankshaft Position Sensor

crankshaft position sensor

The crankshaft position sensor is an engine management component found on virtually all modern vehicles with internal combustion engines. It monitors the position and rotational speed of the crankshaft and sends the information to the computer so that it can make the appropriate adjustments based on the operating conditions. The crankshaft speed and position are some of the most important engine parameters used in engine calculations, and many engines cannot run without it if the crankshaft position sensor is not providing an accurate signal. Usually a problematic crankshaft position sensor will produce a few symptoms that can alert the driver of a potential problem that should be serviced.

1. Issues starting the vehicle

The first symptom that is most commonly associated with a bad or failing crankshaft position sensor are issues starting the vehicle. The crankshaft position sensor monitors the position and speed of the crankshaft and other parameters that play an important role when starting the engine. If the crankshaft position sensor is having a problem, the vehicle may have intermittent starting issues or may not start at all.

2. Intermittent stalling

Another symptom commonly associated with a problematic crankshaft position sensor is intermittent stalling. If the crank position sensor or its wiring have any issues, it can cause the crankshaft signal to be cut off while the engine is running, which can cause the engine to stall. This is usually a symptom of a wiring problem, however a bad crankshaft position sensor can also produce this symptom.

3. Check Engine Light comes on

Another issue of a potential problem with the crankshaft position sensor is an illuminated Check Engine Light. If the computer detects a problem with the crankshaft position sensor’s signal, it will activate the Check Engine Light to alert the driver of the problem. A Check Engine Light can also be set off by a wide variety of other issues so having computer scanned for trouble codes is highly recommended.

The crankshaft position sensor is a very important sensor for proper functionality and performance due to the vital signal it provides for engine calculations. When it has any issues, this can quickly lead to problems that affect the drivability of the vehicle. For this reason, if you suspect that your crankshaft position sensor may be having an issue, have the vehicle inspected by a professional technician, such as one from YourMechanic. They will be able to diagnose your car and replace your crankshaft position sensor if necessary.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.


Post a question and get free advice from our certified mechanics.


More related articles

How Long Does a Fuel Filler Neck Last?
Getting gas from the pump to your gas tank is the only way to keep a car going. The fuel filler neck is a metal tube that is welded to the...
How to Find the Keyless Code on a Ford Explorer or Mercury Mountaineer
Many Ford Explorers and Mercury Mountaineers were manufactured with an option known as the Ford keyless entry keypad. Some models refer to it as SecuriCode as well. It...
How to Buy Fuel Treatments
Adding a fuel additive to your gas tank when you fill up is one way to clean vital engine parts of deposits, improve the performance of your engine,...

Related questions

Q: My 93 Ford Explorer hesitates when opening the throttle, it is very sluggish and acts like it has no power. Then all of a sudden i

You are correct to suspect the MAF with this sort of symptom. The MAF detects the the amount of air entering the motor. If there is a vacuum leak, or more common, if the air boot that connects the MAF...

Q: Car is misfiring

It sounds to me like you have a wire connector issue with the ignition coil pins. The male and female sides fit too loose and only make partial contact. After driving a while a small amount of corrosion forms in...

Q: Issue

It sounds as if you have multiple problems. I would begin by charging the battery and keep the charger on it until you get the truck to run. If the truck died and there were not any lights illuminated...