Can anybody tell me where exactly the knock sensor is on a 5-spd 99 SE-L? Also, what does the knock sensor do? And why is it called knock sensor...any particular reason? Does it make a knocking noise when defective by any chance?

 

It's under the intake runners closer to the drivers side of the car.

If your a cali spec, you woun't be able to see it because it's view is blocked by the swish valve actuator.

It's called a knock sensor because it detects engine knock caused by detonation. Once it detects knock, your cars ECU will adjust the timing to make the knock stop. Knock = BAD

 

go to my website -- click on "Help with Maximas" and I have a few
pics of what the KS looks like, and where it is on your engine...

as for what it does, you can use the SEARCH or:

-- Knock Sensor checks for engine knock.
-- Knock is caused by using bad gas that detonates too early.
Early detonation is usually caused by too low an octane.
-- when knock is detected, the engine changes it's timing to
compensate for the knock, and will rob you of power.
-- when defective, you get a code...or you can use an altimeter
to find out if it's bad.

that's off the top of my head...don't quote me on that stuff either.

good luck!
FLO_BOY

 

 

Black thing in the middle:

 

Flo_boy, that's a sweet ride you have there.

 

thanks man!!!

FLO_BOY

 

You can test the knock sensor with a Volt-Ohm meterm or multimeter.

An altimeter is the guage that tells you at what altitude your plane is flying.

 

uh, right.
just trying to keep everyone on their toes

FLO_BOY

 

Would even funnier if I was up in the Cessna, and my altimiter read 470k Ohms.

 

taking the KS out of there is realy easy.... it took me like 2 mins to do it.. but what i can't do is is unplug the harness of the damn KS... any ideas how to do that??? please help

 

There is a 'U' shaped metal clip that goes around the wiring harness. You need to pull that off with a pair of pliers (or something) to get the harness off.

 

mine just unclips...

FLO_BOY

 

OHhh that's how you do it... lol thank you very very much for the help