I have a 2006 manual transmission, it just clicked over 160,000 km and I've had it since 90,000 km. In the past I've had 2 CELs for SSV stuck closed, both of which were in -20°C weather and cleared up once it warmed up.

Just recently I got CEL P0327 for knock sensor. I cleared the code and it hasn't come back in 2 days. When I read about knocking most people said that couldn't be heard that idle, I definitely hear a repeated knocking/clicking at idle but I don't hear it while driving. No loss in performance felt either.

Given the history of the CELs I thought that it would be a good idea to clean the SSV and change the ignition, since that is a recommended fix for knocking and ssv issues. Ignition was changed when I bought the car so I am due. I just wanted to get your thoughts before spending the time and money.

 

Your ignition is due almost twice over. However that wouldn't really explain knocking. Are you sure what you're heading is engine knock and not some other regular noise from the engine?

 

The service manual says to change plugs every 60,000km (37,500 miles) so I am 10,000km (6000 miles) over due. Unless you are suggesting that they be replaced much more frequently?

I'm not 100% certain that what I hear is knocking, but coupled with the CEL for knocking that's kind of what I thought first. I'll try to get a video but it's been so windy and rainy the past couple days the audio gets drowned out. It sounds almost identical to this which comments are saying clean ssv

https://youtu.be/lw0Tjx2X6cI

When I got the knock cel I was heading to work in the morning, the car had warmed up for 2-3 minutes but wasn't "half way warm" on the gauge.

 

P0327 is for a sensor malfunction.
DTC P0327

The conventional wisdom (correct or otherwise) is that coils and plugs last around 30k miles. I have a hunch that it is significantly longer than that but people tend to underestimate due to the engine-destroying consequences that come from bad ignition components.

 

Plugs AND igntion coils every 40000km. The service manual is.. optimistic about the survivability of stock coils. Failing coils kill engines without symptoms until its too late. You can confirm the state of your spark plugs by pulling them out, I suspect they'll be pretty crusty.

The sound in the video is not engine knock. Try to localize the source using a stick of wood applied to your ear at one end and various engine parts at the other end. When you touch the source, you will hear it clearly through the stick. Like a stethoscope. I suspect a noisy injector, most RX8s make a similar sound. Most cars make a similar sound.

You may want to read up on the new and potential owners thread stickied in the new member section.