what does a knock sensor tell you about problems with an engine?

The knock sensor is like an electronic ear that is bolted to the side of your engine. It listens for the signs of pre-ignition and detonation within the engine. This send a signal to the engine computer to retard ignition timing to prevent engine deterioration based upon detonation. Since you have NOT mentioned what kind of car this is, I cannot give you more details

It means the knock sensor needs to be replaced. There's no fix to a knock sensor. It doesn't tell you about a problem but provides a function by retarding ignition timing when the combustion chambers sense pre-ignition or spark knock.

Some malfunctioning oxygen sensors (Toyota) destroy automatic transmission shift patterns. Instead of starting in low gear the transmission starts in second. The'll also not roll out of fourth gear into overdrive.

Dumping in high test gas doesn't fix or band-aid an oxygen sensor.

Must be a Nissan. Replace the knock sensor.

Unless it's a 1937 Desoto then there is no knock sensor but how would I know what you drive since you didn't mention it.

I fix cars for a living and replace 1 nissan knock sensor a week and rarely have ever replaced any knock sensor from another make. But what do I know, I fix cars for a living and am not a magazine editor.

The knock sensor doesn't tell you anything, it retards the timing when bad gasoline is present. If the engine indeeds knocks, you need a new one. Me and Robert are 200 % correct

Some vehicles have high failure rates on the knock sensor. Nissan and Subaru are two of them.

You need to find a reliable mechanic soon.

Have you checked your engine oil recently?

If you are unmarried, ask your Dad or a brother this question.

Good luck...

First, erase the code and step up to the next higher grade gasoline.