It appears my knock sensor is leaking oil or something. Is this right? Does oil flow through it?

 

No, there's no oil, no water, no fuel...
Nothing can leak from the knock sensor.

 

that might be oil drainage from oil filter changes that runs down there.

Tim

 

There is some plastic/rubber goo that is inside of the knock sensor that can melt if it gets hot. That could me what it is.

 

I don't think oil filter changes have anything to do with it since it's to far away from the knock sensor.

Is it really a fact that the plastic substance in the sensor can melt? Sounds pretty weird..

One thought that came to my mind is that the oil filler neck is almost right on top of the knock sensor.
If you spill som oil there, it might very well end up on the sensor.
There is also a oil line connection in the same area...

 

You are right, it is some type of melted rubber goo. Does this mean I need to replace the knock sensor? At $191 from Mazda, I hope not

 

ttt

 

If you are not getting a code I would just leave it be. Mine was leaking that goo so I went ahead and replaced, but I was putting a new engine in at the time.

 

That goo helps keep the overal sensativity of the sensor down. My old one took a crap and my readings were always much much higher than other people with similar mods. I would suggest replacing it.

 

1. Ok... First of all, NO TO THE OIL Question.

2. The Knock sensor is nothing more than a switch that responds to noise, in this case weird explosions in your engine. It's threaded into a "BLIND" hole that is nothing more than a drilled hole into the side of the engine block. It's only a mounting point. The hole isn't connected to anything. Its tapped (threaded) to accept the knock sensor. That's it!

3. If your knock sensor was bad you'd know it! You'd get a "hard-code" (that's when your idiot light stays on after cycling the ignition key on) and your car would go into or run in SAFE MODE.... Once in this mode, You wouldn't make much boost and the car would run RICH as hell.

4. Now for the presence of OIL and it's likely source.... TOMCO78 was right about the oil filler neck location. It's directly over the knock sensor and can get wet from accidental oil spills.

5. However, another "oil-leak" culprit could be the short Hydraulic line (hose) under your power steering pump. If this thing springs a SLOW leak, you'll think you have the EXXON VALDEZ under your hood. This hose is only 3 inches or so long and connects the power steering main "metal" body housing to its' oil reservoir. The hose ends are secured by those Japanese wire clamps, which tend to dig into the hose over time. The result is usually a slight annoying hydraulic-oil leak. BTW hydraulic oil can be tough on your spark plug wires! it's corrosive to certain types of rubber products.

Anyway, good luck and hope that helps.

 

Well, I'm not getting any check engine codes/light, so I guess I'll just let it be.

 

Yeah.... If it ain't broke... don't fix it

 

i happen to know my hose between the power steering pump and reservoir is leaking. however i have been having a hard time locating a replacement. the dealer wants me to purchase a whole new power steering pump. does anyone know what diameter hose or where i can get a new piece?

 

I think I use 5/8" heater hose to replace mine.