Puzzler time. Here we go. 

As we all know, there are probably 1000s of automotive terms, words that are associated with automobiles. 

We are looking for those precious few words whose secondary meanings, their non-automotive meanings are synonymous with another word which is also part of a car. That wasn't very clear...

We are looking for pairs of words that are parts or systems of your car whose secondary meanings happen to be synonyms. 

Here is an example. 

The word tire and the word exhaust. 

The first meaning of these words is automotive. But the second meaning of these words, to be tired or exhausted, are synonyms. 

Their automotive meanings don't have anything to do with each other. But their secondary meanings are synonyms. 

Here is another example.

The word booster and the word fan. Automotive meaning is different, secondary meaning are synonyms. 

Another one, cable and transmission. 

So with all these examples, we are looking for pairs of words that have automotive meanings, but their secondary meanings are synonyms.

Good luck.