The Toyota 4A engine series was a 1587 cc (1.6 L) inline-four piston engine of the water-cooled four-cylinder inline type. The 4A engine series was introduced in 1988, replacing the outgoing 2T and 3T engines. All 4A engines were built at Toyota's Kamigo Plant in Toyota City, Japan. Production of the 4A series ended in 2001 in Japan, when it was replaced by the ZZ series engine.
Inline-four piston engines are inherently balanced due to their even number of cylinders and opposing firing order, resulting in smooth operation and reduced vibration. The 4AGE engine is no different – it is a very well balanced engine that runs smoothly and produces little vibration.
One reason the 4AGE engine is so good is because it features dual overhead camshafts (DOHC). DOHC allows for more precise control over valve timing and lift, which results in better airflow into the cylinders and thus more power output. The tradeoff for this extra power is slightly increased fuel consumption and emissions, but overall the benefits outweigh the drawbacks.
Another key feature of the 4AGE engine is its use of electronic fuel injection (EFI). EFI provides several advantages over carbureted fuel systems, including improved fuel economy, lower emissions, and easier starting in cold weather conditions. Overall, EFI helps to make the 4AGE a more efficient and cleaner running engine.