Hi all. Just purchased a verada awd. It's making a knocking noise towards the top of the engine. Not the tappet cover. Oil pressure good. Car is great except this noise. It does go away after a while. Question : emission control valve?

When does it do it? Cold or hot engine? How long for? What kind of frequency and pitch is the knock?
There are many variables.

What Ammety said above. Was it knocking when you bought it or did it develop later? I guess you have checked oil levels. Does it do it when standing still or when you are moving?

Just had a thought and it seems to be a common problem, it could be the timing belt tensioner. It has been covered here in the forums, symptoms are a rattle on start up and to see if it is simply switch off motor for 10 seconds and restart motor, if it goes away the tensioner is knackered.

Sometimes the belts make noises

Hot or cold. Starts up great, and the noise goes away until you accelerate. Noticed a disconnected lead so going to replace all leads, clean the plugs and see what happens.

Very high pitch knock also. Thought sticky lifters but they seem fine...