Loud when start and tick when accelerate

I have a 2000 LS-V8 with 96k miles. I've had it 18 months and *knock on wood* I've had relatively few problems. Recently, though, I've noticed that it seems louder than it should when I first start it. It starts fine and runs normally, but it just seems louder than it should. Once the car warms up, I don't notice the noise quite so much - especially at an idle. If I'm driving beside a building and I accelerate (like through a fast food window) I can hear a ticking noise - I hear this same noise when I'm standing outside and my spouse accelerates away. It's not incredibly loud or particularly annoying, but it's enough to know that it should not be there. The noise seems to come from the front to middle of the car and from lower towards the ground. My gut instinct is that this could be exhaust manifold. Thoughts??

I've been hearing another noise (maybe I over analyze??) that seems to have started around the same time. It's not loud enough that I can hear it when I'm driving or even if I'm sitting with the window closed. But, if I open the driver's side door when the car is running (parked, in idle) I hear a noise that seems to be coming from just in front of the driver's side windshield wiper. It sounds like a fast, steady clicking. My dad tells me it's the fuel injectors, but it seems like they shouldn't be that loud. Thoughts on this??

I have the same ticking problem when driving around with my windows down. 2002 v-8 the car has ticked since the day i got it. Would be great to know how to fix this problem.

The injectors are pretty loud. They are fast ticking sound that varies with engine speed.

Pulleys are a coomon source of noise. Being winter (don't know where you're located), it could simply be thick lubricant. Try lowering your oil viscosity to 5-w30 or a full synthetic of the standard 10-w30. Manifolds have been known to tick during warm-up if cracked, but that noise goes away once the car is warmed up. I would aslo check the inner fender plastic skirts/splash shields, exhaust heat shields, exhaust pipe routing, for any loose panels or shielding and potential for stuff to bang and rub if the engine lopes or vibrates. Allow a MINIMUM 1/4" between pipe/fittings and body structures/shields. 1/2" would be better.

The injectors are pretty loud. They are fast ticking sound that varies with engine speed.

Pulleys are a coomon source of noise. Being winter (don't know where you're located), it could simply be thick lubricant. Try lowering your oil viscosity to 5-w30 or a full synthetic of the standard 10-w30. Manifolds have been known to tick during warm-up if cracked, but that noise goes away once the car is warmed up. I would aslo check the inner fender plastic skirts/splash shields, exhaust heat shields, exhaust pipe routing, for any loose panels or shielding and potential for stuff to bang and rub if the engine lopes or vibrates. Allow a MINIMUM 1/4" between pipe/fittings and body structures/shields. 1/2" would be better.

To me, it sounds like exhaust making the noise - but, I realize it's really hard to tell. I live in a cold weather climate and it's definitely louder when the car is cold and seems to minimize when the car warms up. I don't know if this could be related, but I have noticed on a very few occasions that the exhaust fan will come on and accelerate/decelerate in tune with RPM's.