When I start my 2004 suzuki forenza sometimes there is a loud squealing noise that will stop if I rev the engine. It doesn't sound like a belt to me sounds more mechanical. It also sometimes makes the same noise when I slow down to stop and again I'll rev the engine and it will stop

SOURCE: 06 Suzuki Forenza make a loud clicking noise.

Your car is from 2006 how come it needs a timing belt ( do you drive 20K per year? ). What is wrong with the drive belt. The sound from belt is not a clicking noise.
Any way try to avoid that dealer. What a baloney.

When you start the car, open the hood try to identify where the noise comes from.

1-If it comes from the top engine, open your oil cap, to see if oils splattered from mechanical movements. Usually oil is not enough then it takes time to travel to the cam shaft and the lifters that why after making noise a while then the engine becomes quite since it gets lubricated. How long have you been from last oil changed?

2-If it comes from the front engine try to identify if it comes from Power steering or AC. Check Power-steering fluid to see it it needs filled up. Check this before starting the engine.
Try to turn on AC to see if the noise more or less so you can determine the AC clutch is bad.

Hope you can find the source for a good fix.

SOURCE: my 2006 suzuki forenza after driving a few miles,

if your fuel pump was failing you would have engine problems the supply of fuel would be interupted, I would guess that you have a wheel bearing that is worn out you can check this yourself by jacking the rear of the car up wheel off the ground one side at a time,take the wheel with one hand 9o'clock and other 3 o'clock and try moving it back and forth if there is any movement at all even just a little you need a new wheel bearing after you drive a few miles it heat up and make a humming grinding noise that seems to correspond with your speed ,speed up it gets louder and faster ,slow down it it slows down . they are costly but your safety is at risk and others safety is to.get it taking care of asap .

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