I recently had my check engine light come on and it said knock sensor bank 2 circuit 2 I'm not sure where it's located, if there's anyone who can point out where it is, or provide a diagram for me that would be great, and also is it hard to get to? thanks!

The knock sensors are on the top of the engine. I believe bank 2 is under the intake. I had mine go about 2 years ago, but it was easy (bank 1 is a clean shot so I didn't have to remove the intake). Often it's the wiring/plug and not the actual sensor so inspect it closely.

Do you have a picture or diagram to show where it is at exactly? I took it to a shop and they said it was inside the engine cover? They wanted 300 bucks to change it out and wiring etc...

No pics or diagrams here, but you may find some in the FSM. They're in the valley of the engine on top. $300 is about right, but if that shop thinks an intake is an engine cover, you need to take it to someone who knows WTF they're doing.

I think I'll have my brother take a look at it, do you think it's a hard job to do? Do I have to take alot of things apart?

It's not that hard, just follow directions and use a good torque wrench. Here's a good link for the FSM:
http://www.ncttora.com/fsm/1996/SIL/fsm/repair.html

The knock sensors on the 5VZ are located in the V of the engine under the intake manifold.

There is one screwed into a fitting in each side near the center cylinder in each bank. To access them you will need to remove the intake manifold.

While you are in there I would recommend replacing both of them and the wire harness that goes to both of them.

G

I have had so extreme water action in my 4runner and i know from removing the intake that the top of the engine can pool up with some coolant for the bottom of the TB and also in my more recent case water. Though I am not getting a code but it is knocking and sputtering like mad.

If it is not throwing the code, then your knock sensors are probably fine. I really don't understand your question though. Did you drive though a big puddle of water or did you get some bad gas that might have some water in it?

I had a small pond on top of my engine and i was just wondering if the water could have messed up the sensors. I havent had the CEL checked out its always on the the ecu resets its self all the time but yeah I did go through some deep water had water go up over the hood on the drivers side for a second when i went through a hole.

hey guys so I'm having issues again with my knock sensor...had it fixed but I guess my dad's mechanic used a cheap part and it only lasted 1 year. Is there any pics or step by step instructions on how to replace it? I couldn't find any still..

When I went to the dealer they said there's two different brands.

Powertrain control, Knock sensor
4-Runner, 6 Cylinder, Matusita
ELECTRICAL »Powertrain control
Toyota › 4 runner › 1995-2002
List Price : $190.41
Your Price : $142.81


Powertrain control, Knock sensor
4-Runner, 6 Cylinder, Nippondenso
ELECTRICAL »Powertrain control
Toyota › 4 runner › 1995-2002
List Price : $190.41
Your Price : $142.81

can't I just use both denso? Has anyone replaced their knock sensors recently? Almost 2,000 views I'm sure some one has lol.

anyone?

There is quite a bit of work getting to the knock sensors but its not hard. you just need 2 to 4 hrs on hand to disassemble and reassemble. You have to:
1 - drain the radiator by disconnecting the lower hose.
2 - remove throttle body unit, and hoses
3 - remove intake manifold, and hoses
4 - remove fuel injector rail and injectors
5 - now to the knock sensors, The lower part of the intake where the fuel injectors were installed, has to come off to get to the Knock sensors.
6 - Remove the 10 to 12 screws plus 2 nuts in front and 2 in back that secures that lower intake unit.
7 - lift out the lower intake unit out and you will find the 2 knock sensors 1 screwed to the left side of the engine and 1 to the right. If you didn't drain the antifreeze, it will spill out when you lift the intake out. 22 or 23 mm open end wrench to remove the sensors.

Hope this helps someone!

I know your post is old but Brian gave you the link for your answer. Scroll down about half way and you'll see knock sensor inspection. It has the procedures on how to remove those sensors.