Mazda 6 noise under the hood

I have a 2007 Mazda 6 with 133000 miles on it. Recently it has started making a very loud sound that comes from under the hood. The sounds is comparable to the sound a semi truck makes if it is idling. The noise is not constant, usually happens when I put the car in park or if I’m driving at low speed (under 20mph). The sound lasts around one minute. I do not have very much money and am scared what this might cost. Any help would be appreciated!

Have You Checked All Underhood Fluid Levels When The Engine Is Cold And Found The Levels To Be Sufficient According To Your Owner’s Manual ? That’s The First Thing.

Does it make a tinny tink, tink, tink sound ? Does your Owner’s Manual specify regular gasoline, require higher octane gasoline or recommend its use ? What does it say ?

It could be the famous old loose heat shield, honestly.

Not finding out because you don’t have much money and you’re scared, could cost you much more if it turns out to be anything serious. Somehow, you need to find out what it is.

CSA

Does Your Car’s “Date Of Manufacture Sticker” Show That The Car Was Built Before October, 2006 (Early 2007 Model-Year) ?

Mazda says some Mazda 6 3.0L engine vehicles suffer from ticking purge valves during low speed acceleration. There’s a fix for it. Later built cars had the revised parts. If that’s it then it’s really just an annoyance and nothing broken.

CSA