How Do I Know My Porsche Speed Sensor Is About To Fail?

There are two main types of car speed sensors. There’s the engine speed sensor, then there’s the vehicle speed sensor. Each of these sensors plays a different role. Interestingly though, people often confuse the two to mean one and the same thing. Here’s what makes these two sensors different. The engine speed sensor is installed on the transaxle or on the transmission. The vehicle speed sensor on the other hand is installed on the knuckle arm of all the four wheels. Both sensors sometimes fail. Both exude specific red flags before ultimately failing. For the speed sensor though, the consequences can be devastating if not fixed as soon as they’re noticed.

Your Porsche’s transmission is designed to smoothly shift with the help of a healthy speed sensor. The sensor counts how many revolutions take place inside the transmission. As a result, the control unit of your Porsche transmission receives data then proceeds to make the necessary adjustments after capturing and calculating the rotational speed. This is what you read on the gauge on your Porsche’s display. Read on to learn more about the tale tell signs of a failing Porsche speed sensor and the solutions you should try.

Rough Gear Changes

This stands out as one of the most common symptoms of a failing speed sensor. The transmission simply fails to smoothly change gears because of high transmission revs. This is bad for both the engine as well as the gear box because it means the car engine runs faster than the car itself. Ultimately, the speed sensor ends up failing.  Note that at the initial stages of the problem, you may still be able to shift gears without a problem. But as the problem worsens, you will have a hard time shifting into higher gears. Eventually, the transmission will keep on engaging into overdrive late.

Check Engine Light On

The dreaded check engine light can easily be triggered by a failing or an already failed speed sensor. It may light up and stay or light up intermittently. Either way, the check engine light turning on with the P0500 code is a sure sign that there’s something wrong with the speed sensor. The problem will worsen each time you accelerate. To be sure what or which code accompanies the check engine sign, have the problem assessed and diagnosed by a qualified Porsche technician. Alternatively, you can use an OBD scanner or a Porsche endorsed diagnostic tool.

The Solution

Unfortunately, it is not possible to repair a failed speed sensor. The best you can do is to simply replace it with a new one. It is also important to note that this is not a Do It Yourself project. Like already hinted, have a mechanic assist you diagnose and fix the speed sensor problem. Then while at it, always remember that a faulty speed sensor is a safety issue. The last thing you want is to over speed simply because you cannot tell from the display how fast you are driving. This alone explains why you should take speed sensor issues seriously.