95 240sx Knock Sensor Problems Please Help

[drifter92]

I installed headers, a catback exhaust, and a ram intake on my 1995 240sx, ran it with no headers and now i have a Knock Sensor coming up on the code reader... At idle, sometimes theres a metal rattle coming from under the firewall on the driver's side. I havent been able to place the sound but it's not coming from inside the engine.Tell me what you think...Click here for pictures of my car... http://www.cardomain.com/ride/2956195

[redchile]

Clear the code and if it comes on again then replace the sensor. Mine just went out and had to be replaced as well on my '95. Auto zone sells it for $165.

[drifter92]

I figured it was just the sensor, thanks.

[theother1wstolen]

ive heard from a few different people that running a car with no exhaust mani on it can make it suck in cold air when you shut it off cracking one of the exhaust valves, but ive never seen it happen first hand so i cant say 100% that its true.

[ELEMENT692121]

first off find out where the noise is coming from .. a loud rattle can be interpreted by your ecu as excessive knock and strigger a knock code.. ive seen it time and time again on sti,s there is a messed up piece of heat shield on them and it will make your car slow as hell and trigger a code ..

[ELEMENT692121]

ive heard from a few different people that running a car with no exhaust mani on it can make it suck in cold air when you shut it off cracking one of the exhaust valves, but ive never seen it happen first hand so i cant say 100% that its true.

it dosnt suck in cold air and crack a valve the lack of any backpressure at all can allow the hot exaust gasses to escape so fast across a single point on a valve it will burn a piece of the valve away ..