What would cause a rattling scraping noise to be coming from under my hood?

Question

it makes the noise idle and while moving, yet the car drives normally. There is nothing under the car that could be scraping.

Answer 1

It could be a heat shield that came loose. I have had that happen a couple times on different cars. Most recently my wife's Nissan quest. A heat shield does exactly that, shileds heat from a hot part to the parts mounted near it. They are not absolutely necessary but usually required by the government in order for a car to be approved for production because soemthing could happen, although not likely. You need to really get in the engine and under the car to investigate, try to touch/grab/manahndle everything to find out if something is loose. You can save hundreds by not taking it to the dealer.

Answer 2

I would take it to a auto shop and have someone look at it and quote it.  Quotes usually are free.  Rather you have them work on it or not, they will till you where your problem lies.  I would almost question that it's the timing belt or gears.  Not sure of the type of car it is so I'd only be guessing.  Take it somewhere and let them quote you.  This is what I did.  Once they told me for sure I bought the parts myself and had my brother fix it for me.

Answer 3

Could be a number of things

1. Water pump

2. A/C clutch

3. Alternator

4. Serpentine belt idler pulley

5. Power Steering Pump

Remove the serpentine belt.  Start the engine, if sound is gone then one of the above items needs attention.

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Answer 4

check tail pipes and mufflers