chedeng1152

My CarMd scanner shows a diagnostic Code of P0325 indicates a fault in Bank 1 sensor 1 electrical circuit for a predetermined period of time.
I would like to replace the knock sensor but don't know the location.
I need help to tell me where is the location of the knock sensor 1.
Thanks.

Plutoe

It is not a simple task---first remove the intake manifold and you will see the R and L knock sensor bolted to the center of the block!!

chedeng1152

I know this is not a simple task but I would like to do it to save me bucks. Which one is no. 1 knock sensor. Thanks for the help Plutoe.

Plutoe

When sitting in the drivers seat number 1 is on the right and 2 is on the left--the torque is 20Nm---however if I were you I would change both!!

chedeng1152

Thanks again Plutoe for the info.

wallyp

My experience has been that the connections are much more likely to be the problem.

chedeng1152

I guess I should start from the outside of intake manifold. Can you tell me where to check for connection wires to knock sensor?

chedeng1152

I removed the two old knock sensors and copared the reading with the new sensors. I get 1.93M onthe 2 old sensors and 1.89M for the new sensors. When I check the continuity of the wires there is continuity on the left and and open on the right.
I have other problem. When I removed the intake manifold I did not notice if the front left hole on the engine has cover. See photos.
Any idea if the hole is open. I cannot find the parts in my inventory.

wallyp

I believe that opening is for the secondary air injection from the electric pump on the top front of the engine. There are two check valves and two vacuum-operated valves, one on the front of each of the heads.

chedeng1152

So this hole is the exhaust for the injection pump? I did not pay attention when I removed the intake manifold because there was no connected part to it.

chedeng1152

For S430 4Matic owners, can you tell me if the hole has plug or connected to any part?
Thanks.

wallyp

See Post #9.

chedeng1152

So this hole is for the exhaust of the secondary air injection pump?
No cover is attached to it. Please verify yes or no.
Thank you for you help Wallyp.

wallyp

On my S430, there is a check valve bolted in that location. The check valve feeds into the intake ports. The check valve is plumbed to the secondary air injection pump.

chedeng1152

Thanks for the information.
One last question. Just answer yes or no. Referring to the picture I posted the one I circled. Is this port has cover? Yes or no.
Thanks again Wallyp

wallyp

I have answered the question twice in detail. That opening has a pneumatic check valve bolted over it. That covers the port.