I personally wouldn't try to diagnose a VVT/ECU electrical system with no relevant experience. Usually with these things, mechanic with experience on this particular system probably will know where to look to come up with the correct corse of action - while I'd just begin shooting the "parts cannon". And there are many guys on the forms that have replaced thousands of dollars of expensive parts and it ends up being a wire, or a junction box, or something else...

If you some have experience working on cars, it might be a good idea to try fixing yourself - at your own risk

If you don't know what you're doing, I wouldn't advise trying to do anything complex.

IMO It's best to try to find a good mechanic...

What is the WHOLE diagnostic result please?