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Changing Knock Sensor @00 Ls 400?

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Hallo together,

first please excuse my bad English.

My Name is Holger I´m from Germany and I did bought (may not a good deal) a 00 LS 400 with low mileage.

but it seems the knock Sensor is not working.

OBD Error: P0325 - Generic

Type Powertrain - Ignition System or Misfire - ISO/SAE Controlled
Knock Sensor 1 Circuit
Location Bank 1 or Single Sensor

I did found by searching:


You can change the knock sensors and wire harness without removing the intake manifold. Remove the EGR valve, PCV hose and you can get you hand into the V area of the block. A 27mm socket and small rachet with a flex head and the job is done.

and in an other board:


IThe good news is that I just finished changing the right-side knock sensor, and the problem is fixed (no more pinging). It was fairly easy to change the sensor. The whole job including test drives took about 1 1/2 hours. I removed a couple of the plastic cover pieces between the manifold and the valve cover, and with a long screwdriver, gently removed the connector on the sensor (accessed on the right side of the engine thru the small openings around the manifold). I removed the knock sensor using a long 3/8 extension with a universal joint and a 1 1/16" sensor socket taped together to hold the tools together. I installed the new sensor using tape on the socket to hold it in place. FYI - The sensors are very tight in the block

Read more:


So my question i did not find an Answer:

does this way to do the work similar with the VVTI Engine in the Late LS400? (Both up are for the older Engines)

and may if any ever did change in the late Engine, did you use an OEM Part without Problems?

Thank You!

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Those links are to Generation 1 LS 400s (89-94) you have a Gen 2 LS (95-00). You have to remove the intake manifold to get to the knock sensors. It states this in the repair manual and from my own experience changing out the starter which is where both sensors are located I don't see how you would remove them without removing the intake manifold. I don't know how they accomplished it on the Gen 1 but the designs are similar but I guess there are some small differences. I guess you could try to fit something through the 2 side openings on the manifold that yo can see in pic 2. By the way that's a view from underneath the manifold.





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  • 2 years later...

"You can change the knock sensors and wire harness without removing the intake manifold. Remove the EGR valve, PCV hose and you can get you hand into the V area of the block. A 27mm socket and small rachet with a flex head and the job is done. "

I tried this method before, it worked but costed me 2 broken connectors. I then had to remove the manifold to replace the connectors. Unless your hands are very small, there isn't much room to unlock & pull the connectors.

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  • 3 years later...

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