BATMAN

ok.. from what i read in the Search..

the knock Senor is something to prevent Detination..
but.. what else does this knock senor do?

also.. i have this problem.. where i have a oil leak from the spark plug side of the engine... a friend of mine tells me as the car ages. and the knock senor gets old... it leaks. now.. isnt a knock senor a simple wire... how the hell can that leak?

weird... well when i get some time i will try to post pics maybe you all can help me.

Dougie_fresh_007

the sensor does not do anything cept tell the ecu how much noise is commin from there... if u get a power fc it will give u a number but all it does it monitor noise... so its not the msot accurate thing in the world

Nathan Kwok

What is probably happening is the glue or whatever that junk that holds the knock sensor in is melting and leaking out. The sensor is essentially a small microphone that plugs into the rotor housing below the spark plugs. This is a common problem and basically you have to replace the sensor. The engine does react to the knock input to prevent detonation, but not very well. If you are asking if you can just remove it and plug the hole, no you can't, you need to replace it. If you want better knock sensing, get a J&S, but first I'd fix the leak, and if the leak is coming from the knock sensor, replace it.

BATMAN

alright cool.. i just checked it is that seal.. from the knock sensor.. thanks for the info... it was a lil messy to get to.. and dint have the time b4..

also a Quick Question about the J/s Knock Sensor..
you said the knock sensor is a mic. right?.. so how would a mic "retard" a spark from happening? sorry if i am a lil dense

Rx-7sotre.net : "Preignition is the #1 killer of turbocharged rotaries. The J&S System is used to help warn/save your motor from preignition and prevent costly engine rebuilds. The unit we offer has been specifically designed for the rotary engine and has the capability of retarding the timing on the rotor face that is causing the preignition."

BATMAN

ok i was thinkin about it while i was in the shower..
the knock senor can hear the plugs firing and just can delay the spark..?.... if so .. damn thats alot of math.. invovled....

so the unit does it automaticly or do you have to set it manually?

Nathan Kwok

The J&S you have to set manually. It has a readout telling you how many degrees of timing its taking out, and the idea is you drive around with it and eventually set it up so it just barely doesn't take out timing. That way when the real detonation occurs it'll definitely take out a lot of timing. My own experience and that of others shows that the unit is very sensitive, but its not foolproof. The biggest shortcoming of the J&S is that it doesn't alter the trailing ignition, only leading, and detonation can occur at the trailing plug too. However, the stock sensor is regarded as being pretty useless, not to mention its on the front rotor when most problems occur on the rear rotor, so adding a J&S to the rear is a nice upgrade.

Nathan Kwok

Oh, to answer the question about how it works, its not preemptive, that is, it has to hear the detonation first and then react. However, the mic is so sensitive that it can detect detonation long before you would hear it audibly, and it reacts very fast, so the idea is it'll intervene before serious damage occurs.