On a cold start I get a tapping/clicking noise from the engine, I'm assuming the valves. At higher RPMs or after it warms up, it goes away.

Any ideas?

 

It might be the VTC's

 

can you explain more?

Is it something I can fix or do I need to take it into the shop?

 

VTC's are probably one of the most common problems on this board.You can have them rebuilt but i believe it costs alot. however most people who have this problem have resorted to just grounding them. craig brace has a nice write up http://www.geocities.com/craigbrace/ on how to do this. but be warned there is a little bit of power loss, but nothing too bad. if you don't want to lose that power there is also a write up by (i think)mrgone that uses an on/off switch to control when they are grounded, I can't find the link but maybe someone else knows where it is.

 

If you ground the VTC's, some people have reported to idle flucuations right after grounding the VTC's but overtime the ECU should adjust to it.

 

I had idle problems when I grounded my VTCs. When you ground your VTCs, you do lose some power, too.

Rebuilding them isn't terribly expensive (a few hundred bucks), it's the labor costs that make the job expensive. Most dealerships want a total of $1500 to $2500 total to do the job and I don't think many mom and pop garages would be willing to take on a VTC replacement.

I think there are a few guys here who have done the entire job by themselves and it is somewhat complicated, although not impossible. I think if you have previous experience with taking apart and rebuilding engines, you could do the job. I don't think it's really a job for an amateur unless you are brave enough to risk having to buy a new engine.

 

Is it harmful if the VTC problem is not fixed? Or is it just an annoyance?

 

I haven't heard of any harm coming from not fixing the vtcs, maybe someone else has, besides that i think they are just an annoyance.