El limpiaparabrisas hace ruido cuando llueve mucho, pero funciona bien.

Limpiaparabrisas is a compound noun.

It is built from:

• limpia- = from limpiar (to clean)
• parabrisas = windshield / windscreen

So literally it is something like windshield-cleaner, which in natural English is windshield wiper.

Spanish often forms object names this way:

• abrelatas = can opener
• sacacorchos = corkscrew
• paraguas = umbrella

The noun is normally masculine, so it takes el in the singular:

• el limpiaparabrisas = the windshield wiper
• los limpiaparabrisas = the windshield wipers

With many compound nouns like this, you just need to learn the gender as part of the word. Here, the standard form is masculine.

Here it is singular because the article is el.

• el limpiaparabrisas = singular
• los limpiaparabrisas = plural

This is one of those Spanish nouns whose form often stays the same in singular and plural, and the article tells you the number.

So in this sentence, el shows that we are talking about one wiper or the wiper system as a single thing, depending on context.

Hacer ruido is a very common expression meaning:

• to make noise
• to be noisy
• to produce a noise

So:

• El limpiaparabrisas hace ruido = The windshield wiper makes noise

This is more natural in Spanish than trying to translate word-for-word from English in another way.

Similar expressions:

• Ese motor hace mucho ruido.
• La puerta hace ruido al abrirse.

Sometimes yes, but the meaning shifts a little.

• hace ruido focuses on producing noise
• suena means sounds and focuses more on how it sounds

For a mechanical problem, hace ruido is very common and natural.

Examples:

• El limpiaparabrisas hace ruido. = The wiper makes noise.
• El limpiaparabrisas suena raro. = The wiper sounds strange.

So hace ruido is a very normal choice here.

Spanish uses the present tense here because this sentence describes a general/habitual situation:

• cuando llueve mucho = when it rains a lot / whenever it rains heavily

It is not talking about one single future event. It means this is what usually happens under that condition.

Compare:

• Cuando llueve mucho, hace ruido. = Whenever it rains a lot, it makes noise.
• Cuando llueva mucho, hará ruido. = When it rains a lot in the future, it will make noise.

So the present tense here is used for a repeated or general fact.

Llover (to rain) is an impersonal verb in Spanish.

That means it is normally used only in the third person singular:

• llueve = it rains
• llovía = it was raining
• lloverá = it will rain

There is no real subject doing the action. It works like English it rains, where it does not refer to anything specific.

So cuando llueve mucho simply means when it rains a lot.

Here mucho means a lot.

In this sentence, it is working like an adverb, modifying llueve:

• llueve mucho = it rains a lot
• more naturally in English here: it rains heavily

Important difference:

• mucho as an adjective changes form:
  • mucha agua = a lot of water
  • muchos coches = many cars
• mucho as an adverb does not change:
  • llueve mucho
  • trabaja mucho
  • me gusta mucho

So here it stays mucho.

Because hacer ruido is a fixed, idiomatic expression.

Spanish often leaves out the article in expressions like this:

• hacer ruido = to make noise
• tener hambre = to be hungry
• tener miedo = to be afraid

If you added an article, the meaning would become more specific:

• hace ruido = it makes noise / it is noisy
• hace un ruido raro = it makes a strange noise
• hace mucho ruido = it makes a lot of noise

So in this sentence, no article is the normal choice.

Pero means but, and it shows a contrast:

• there is a problem: hace ruido
• despite that, the result is positive: funciona bien

So the sentence means:

• it makes noise when it rains a lot, but it works well

If you used y, it would simply add information without highlighting the contrast.

Because funcionar is the normal verb for machines, devices, and systems meaning:

• to work
• to function

So:

• funciona bien = it works well

This is exactly the kind of verb Spanish uses for things like:

• El coche funciona bien.
• La lavadora no funciona.
• El aire acondicionado funciona perfectamente.

For machines, funcionar is usually better than trying to use a verb like trabajar.

Bien is an adverb, and it means well.

It modifies the verb funciona:

• funciona bien = works well

Compare:

• bien = well
• bueno / buena = good

So:

• funciona bien = it works well
• es bueno = it is good

English speakers often mix up bien and bueno, so this is a useful distinction.

Yes, depending on context.

El limpiaparabrisas can refer to:

• one windshield wiper
• the windshield wiper mechanism/system as a single unit

In everyday speech, people may use the singular even when thinking about the wiper as one functional part of the car.

If the speaker clearly wanted to refer to both wipers as separate physical pieces, they could say:

• Los limpiaparabrisas hacen ruido...

But the singular in your sentence is completely natural.

Because the subject is singular:

• El limpiaparabrisas = singular

So the verbs must agree with it:

• hace = it makes / does
• funciona = it works

If the subject were plural, the verbs would change:

• Los limpiaparabrisas hacen ruido..., pero funcionan bien.

This is a good example of subject-verb agreement in Spanish.

Yes.

In this sentence, cuando can be understood as:

• when it rains a lot
• whenever it rains a lot

Because the sentence describes a repeated situation, English often naturally uses whenever even though Spanish just says cuando.

So the idea is general, not just one single moment.