The A Series engines are a family of straight-4

Straight-4

The inline-four engine or straight-four engine is an internal combustion engine with all four cylinders mounted in a straight line, or plane along the crankcase. The single bank of cylinders may be oriented in either a vertical or an inclined plane with all the pistons driving a common crankshaft....

 internal combustion engine

Internal combustion engine

The internal combustion engine is an engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber. In an internal combustion engine, the expansion of the high-temperature and high -pressure gases produced by combustion apply direct force to some component of the engine...

s with displacement from 1.3 L to 1.8 L produced by Toyota Motor Corporation

Toyota Motor Corporation

, , , commonly known simply as Toyota and abbreviated as TMC, is a multinational automaker headquartered in Toyota, Aichi, Japan. In 2010, Toyota Motor Corporation employed 317,734 people worldwide, and was the world's largest automobile manufacturer by production.The company was founded by...

. The series has cast iron engine blocks and aluminum cylinder heads.

The development of the series began in the late 1970s, when Toyota wanted to develop a completely new engine for the Toyota Tercel

Toyota Tercel

The Tercel is a subcompact manufactured from 1978 to 2000 across five generations, in five body configurations — sized between the Corolla and the Starlet...

, successor of Toyota's K engine

Toyota K engine

The Toyota K series was a straight-4 engine produced from 1966 through 1988. It was a 2-valve pushrod engine design, a rarity for the company....

. The goal was to achieve good fuel efficiency and performance with a modern design.