Knock Sensor Question?

Question

Ok I have a 92 honda prelude with a knock sensor code. I know the knock sensor protects the engine and all that good stuff, but my car revs up and down. Its not my IAC because I replaced it with a good IAC. Can it possible be my knock sensor doing that? thanks

I just get a knock sensor code

Answer 1

Knock sensor faults are caused by the knock sensor "Hearing" a noise in the motor called pinging. You can raise the octane level of the gas you use. If your in the highest octane at the gas station you go to, then you have to switch brands. Chevron or 76.

Also if the timing is off, that can cause pinging. Some pinging you cannot hear, but your motor can.

Also it is common for the device itself, the knock sensors, to go bad. Especially if they get oil or carb clean on them.

Answer 2

The knock sensor is not the problem. The knock sensor hears your engine "pinging" and adjusts the timing to compensate. You don't mention a check engine light so we can't work from there. The engine revving would have to be a fuel matter. Something is possibly allowing excess air into the system and the ecm senses it and supplies more fuel. as the engine accelerates the vacuum would drop and the ecm would sense lees air and cut back the fuel. Just a thought.

Answer 3

i agree no its not the knock sensor disconect the battery for one minute that will reboot the computer sounds like a vacum leak look and listen for a sucking hissing sound thats what would make it go up and down like that.

Answer 4

Check the coolant and burp it to make sure it is full.Power steering has a sensor to raise the idle also,vaccum leak is most likely the problem