Hi I am a new user.

I am having a missfiring trouble under hard acceleration with my dad's 2001 S40. I have noticed that the turbo control valve is doing several ticking sound (like a relay) but once or twice every second. This sound only happens when I rev up the engine, it doesn't do it at idle speed.

Is this normal or could it be related to my missfiring?

Is there a way to bypass this valve in order to test it?

 

The TCV is simply controlling the boost. I'm betting you need a tune up. Every time my 2001 has misfired it was either the ignition coils or bad plugs or both.