Knock Sensor

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Long story short, my check engine light is on. I took it to The Lube Center. They said it was the knock sensor. The tech said that it is probably caused by dirty fuel. He suggested bumping up a grade in gas, picking a certain gas station chain and using them all the time, and getting a complete fuel injector cleaning.

Any thoughts from you guys? I already use High Octane gas.

'01 Impreza 2.5RS

posted by  Kardon

heres a description of what the knock sensor does. detect vibrations from cylinders during combustion process the signal is sent to the computer if the vibration is higher than limits the computer will retard the ignition timing to reduce the uncontrolled vibration. thats it so maybe the sensor is bad or you have low octane fuel look in your owners manual or contact the dealer and find out what octane rating is needed for your car if what you are using is an ok rating and your service engine light is coming on then you more than likely have a bad sensor

posted by  osborste

I use high octane gas already.

They turned off the light, and I figure if it comes back on, I'll head to the dealer. See what they say.

I'm kinda iffy about dropping money on the injection cleaning if the sensor is bad.

posted by  Kardon

Would adding something like STP Octane Booster (http://www.stp.com/fuel_oct_boost.html) help? Give that a shot and see if the light stays off?

posted by  Kardon

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