O pedal faz barulho.

Faz comes from the verb fazer, which usually means to do or to make.

In this sentence, fazer barulho is a very common expression meaning to make noise.

So:

• o pedal = the pedal
• faz = makes / does
• barulho = noise

Grammatically, faz is the 3rd person singular of the present tense, because o pedal is singular.

A few useful forms of fazer in the present:

• eu faço
• tu fazes
• ele/ela/você faz
• nós fazemos
• vocês/eles/elas fazem

O is the masculine singular definite article, meaning the.

So o pedal means the pedal, usually a specific pedal already known from the context.

Portuguese uses definite articles more often than English does. In many everyday situations, Portuguese prefers:

• o pedal
• a bicicleta
• o carro

where English might sometimes just say the pedal, or in some contexts even leave things more implicit.

If you remove o and just say pedal faz barulho, that sounds ungrammatical in normal standard Portuguese.

Because fazer barulho is a normal idiomatic expression, and here barulho is being used in a general, uncountable sense: to make noise.

This is actually similar to English, where you often say:

• make noise

not necessarily:

• make a noise

So faz barulho is the natural basic form.

Both are possible, but they are not exactly the same.

• faz barulho = makes noise / is noisy
  
  • general, neutral
• faz um barulho = makes a noise / makes quite a noise
  
  • often more specific or more emphatic

For example:

• O pedal faz barulho. = The pedal makes noise / The pedal is noisy.
• O pedal faz um barulho estranho. = The pedal makes a strange noise.

So adding um often makes the noise sound more concrete, more noticeable, or more dramatic.

Because barulho and som are not the same.

• som = sound, in a neutral sense
• barulho = noise, often unwanted, annoying, or abnormal

So O pedal faz barulho suggests that the pedal is making a noise that you notice and probably do not want.

If you said O pedal faz som, that would sound odd in most normal contexts, because of course a moving pedal can produce sound. The important idea here is that it is making noise.

A rough European Portuguese pronunciation is:

u p-dal fazh ba-ROO-lyu

A few important points:

• O often sounds like u when unstressed.
• pedal is stressed on the last syllable: pe-DAL
• faz is often pronounced like fazh here, because the z comes before b in connected speech
• barulho has lh, which is similar to the lli sound in million, though not exactly the same
• the r in barulho is the Portuguese guttural r

If you want an IPA-style version, one common European Portuguese pronunciation is approximately:

/u pɨˈðaɫ faʒ bɐˈʁuʎu/

Regional accents can change it a bit.

Yes, absolutely.

In European Portuguese, estar a + infinitive is the normal way to express an ongoing action.

So:

• O pedal faz barulho. = The pedal makes noise / The pedal is noisy.
• O pedal está a fazer barulho. = The pedal is making noise.

The first sentence can describe a general fact or a present situation.
The second one focuses more clearly on what is happening right now.

This is a very useful Portugal-vs-Brazil point:

• Portugal: está a fazer
• Brazil: está fazendo

It is grammatically correct, but it is usually less natural in this kind of mechanical context.

For a machine part or a piece of equipment, Portuguese often prefers:

• faz barulho
• está a fazer barulho

rather than:

• é barulhento

Barulhento is common, but it is often more natural for people, places, or things in a broader descriptive way, for example:

• um vizinho barulhento
• uma rua barulhenta
• um restaurante barulhento

So for a pedal, faz barulho is usually the most idiomatic choice.

Sometimes yes, if the context is already very clear.

For example, if two people are looking at a bicycle and one points at the pedal, saying Faz barulho can work as It makes noise.

But on its own, without context, O pedal faz barulho is clearer and more complete.

A useful distinction:

• Portuguese often drops subject pronouns because the verb ending shows the subject.
• But dropping a whole noun phrase like o pedal depends on context, not just grammar.

So:

• O pedal faz barulho. = clear and complete
• Faz barulho. = fine only when the listener already knows what it is

No. Pedal can refer to different kinds of pedals, depending on context.

For example:

• a bicycle pedal
• a car pedal
• a sewing machine pedal
• a guitar effects pedal

So O pedal faz barulho could mean different things depending on the situation. If needed, Portuguese can make it more specific:

• O pedal da bicicleta faz barulho.
• O pedal do travão faz barulho.
• O pedal de efeitos faz barulho.

It becomes:

Os pedais fazem barulho.

Changes:

• o → os
• pedal → pedais
• faz → fazem

So:

• O pedal faz barulho. = The pedal makes noise.
• Os pedais fazem barulho. = The pedals make noise.

Notice that barulho stays singular here, because the expression is still make noise, not make noises.