It's Bumblebee ...

Look what I saw at Xian's ... Nice eh! Anyway, check out my movie review of one of the defining films of the year!

Wikipedia has everything! ... Here's a bio of the Original Mk 1 Bumblebee!

Bumblebee (known as Bumble in Japan) is the "little brother" of the heroic Autobot faction, constantly striving to prove himself in the eyes of the taller, stronger robots that he respects - especially his leader, Optimus Prime. So strong is this admiration toward others, he takes risks that put him in danger. Although a bit of a wise-cracker, he is a capable and reliable messenger and spy, his small size allowing him to go places that his larger comrades cannot. He is highly fuel efficient, has great visual acuity, is particularly adaptable to undersea environments and transforms into a Volkswagen Beetle. He was later reconstructed in a stronger, more mature form as Goldbug.
Bumblebee is established as the smallest of the first year Autobots, but his actual size varies greatly in the various media, ranging from the same size as other Autobot cars to barely taller than a human. His only official height was in an early issue of the Marvel comics where it is stated he is 15 feet tall.