What Happens When Your Audi Q7 Knock Sensor Goes Bad? Q7 is the most popular sport utility vehicle in the Audi lineup. It has a maximum engine power output of 248 horsepower and a torque output of 273 pounds per foot. It's equipped with advanced safety features that make it one of the safest vehicles on road. The integration of cutting-edge sensors and microprocessors made Audi Q7 one of the advanced and powerful SUVs to ride. A knock sensor is one of such sensors that significantly enhance the power output of the engine. If it goes bad, a lot of things can go wrong. A failing knock sensor can adversely affect the power output of the engine. Besides, it would make your Audi Q7 engine consume more fuel than usual. So, let's find out more about the knock sensor and what would happen if it fails.
What’s a knock sensor and what does it do? It’s a small electric device designed to quantify the unusual engine vibration and sound. Simply put, it helps the engine management computer to detect pre-ignition or detonation. The engine control unit or ECU then uses this data to regulate the ignition timing accordingly. Usually, you can find it outside the engine block. But, in some cases, it’s located in the intake manifold. The timing of electric spark generation by the ignition system has to be perfectly synchronized with the timing at which the air-fuel mixture is entering the combustion chamber of the engine. The ECU analyzes the data received from the knock sensor and a dozen of other advanced sensors to maintain that consistency. However, a bad knock sensor might provide inaccurate information to the ECU which would make the engine run rough and abruptly cease operation. Therefore, learn to recognize the signs of a bad knock sensor in your Audi Q7 so that you can replace it on time. But first, let’s discuss some of the most common reasons behind knock sensor failure in your Audi Q7.
What causes knock sensor to go bad? Following reasons are primarily responsible for premature knock sensor failure in your Audi Q7;
Improper installation Damaged connectors Bad piezoelectric metal ring Flawed seismic mass Electric issues
What are the symptoms of a bad knock sensor? Declining engine performance Audi Q7 is powered by a typical internal combustion engine. Its operation is closely monitored and controlled by the ECU. The knock sensor and a dozen of other sensors aid the ECU for a smooth engine operation. However, if the knock sensor goes bad, it would provide misguided data to the ECU. When that happens the engine won't be able to run smoothly and you would notice a loss of acceleration when driving your Audi Q7.
High fuel consumption A bad knock sensor would adversely affect the engine performance. When the ECU finds out that your Audi Q7 engine is not performing well, it would direct the fuel injection system to deliver more fuel into the cylinders. As a result of which, you would notice a significant rise in the rate of fuel consumption in your Audi.
Blinking check engine light
A knock sensor is supposed to sense pre-ignition within the engine and aid the ECU to regulate the ignition timing accordingly. However, if it goes bad, the ECU won’t be able to do that anymore. It would make the engine run rough. When the onboard computer finds out about the issue, it would immediately turn on the check engine light or malfunction indicator lamp on the dash of your Audi Q7. Besides, it might also store error codes (P0325-P0334).
Exhaust emissions increases
A faulty knock sensor can trigger an array of engine problems in your Audi Q7. It would make the engine run rich and emit a lot of unburned hydrocarbons. So, if you’re Audi Q7 is emitting thick black smoke, there’s a good chance its knock sensor is failing and needs to be replaced immediately.
Strange engine noises
In the worst-case scenario, having a worn-out knock sensor can make your Audi Q7 engine run rough and misfire. Besides, you would also hear a strange pinging or knocking sound coming from the engine. If lef unaddressed, a bad knock sensor can cause serious engine-related problems in your Audi Q7.
Bad knock sensor- How to diagnose and fix it? If you're recognizing one or more of the above signs when driving your Audi Q7, there's a good chance its knock sensor has gone bad. You can use an ohmmeter to check its condition. If it's not working properly, get it replaced right away.
Final thoughts A knock sensor essential aids the ECU to regulate the ignition timing. If it fails, your Audi Q7 engine might misfire and abruptly cease operation. So, early warning signs of knock sensor failure in your car should not be overlooked. Schedule an appointment with the nearest auto service center to install a new knock sensor.