Hi, my engine on my N/A Zx has started making a light knock/ tapping sound. The sound is coming from the top passenger side of the engine under the plastic cover. Taps at tickover then goes when the engine is reved and returns for a moment when tickover returns. There is no noise at all during driving and doesnt effect performance in anyway. VVT springs has been a suggestion? how do i check these.

most proberly your lifter. Mine does it when its stood for a while. really annoying

 

Try changing you oil. usually works.

Mine has quietened down a lot also since I used Wynn's lifter treatment,

http://www.ebay.co.uk/itm/WYNNS-Hydraulic-Valve-Lifter-Treatment-8v-16v-24v-12v-/290136699178?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item438d7eb12a (for example) coupled with an oil change.

Well recommended.

Mine has quietened down a lot also since I used Wynn's lifter treatment,

http://www.ebay.co.uk/itm/WYNNS-Hydraulic-Valve-Lifter-Treatment-8v-16v-24v-12v-/290136699178?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item438d7eb12a (for example) coupled with an oil change.

Well recommended.

Thanks, I'll give that a go.

if you are using 10w40 oil try using a 5w40 or 5w50, should cure it.