How to Tell if You Have a Faulty Engine Speed Sensor

Your vehicle's engine speed sensor, or vehicle speed sensor as it is also known, sends information to your car's computer about how fast the car's engine is spinning at any particular moment. The sensor does this by recording how fast the crankshaft of your vehicle is spinning. A faulty speed sensor can cause all sorts of strange problems in your car.

Most Common Symptoms of a Faulty Engine Speed Sensor

A faulty vehicle speed sensor can cause an array of problems. In fact, symptoms of a faulty speed sensor may also result symptoms of other common components such as a defective coil pack or bad throttle position sensor. However, here is a list of the most common symptoms associated with a bad engine speed sensor:

• Transmission revs higher before it changes gears
• The car's transmission engages into overdrive late and sometimes will never go into that top gear
• Brakes are sometimes harder than normal when coasting
• Speedometer behaves erratically or sometimes does not work at all
• The check engine light comes on intermittently and sporadically when accelerating
• The overdrive on/off light blinks on and on for no apparent reason

How to Test the Vehicle Speed Sensor

If your car is experiencing any of the above symptoms, you should take your car into a local dealership to have them run a computer diagnostic on your vehicle. While some of the problems may seem transmission related, it is usually better to take your vehicle to a repair shop that has complete computer diagnostic equipment before going to a specialty repair shop.