Appearing in the United States in 1979, the midsize Mazda 626 was certified by the federal government as a domestic car a decade later. It was placed between Mazda's compact Protege and its luxurious Millenia. The Mazda 6, currently in production, is the successor of the Mazda 626.
The first (1979 to 1982) and second generation (1983 to 1987) Mazda 626s are extremely rare on account of their age. Thus, there is little if any information on vehicle problems for 626s of these eras.
Some third-generation (1988 to 1992) Mazda 626s may have knocking noises coming from the suspension in the event of sharp turns or driving over a bump. This can be resolved with the introduction of a rubber spring seat. Also, there is the possibility of a water leak from the taillight/brake light housing to the trunk, which can be stopped by replacing the seal in that area.
A unique problem of 1990 Mazda 626s is the air-conditioning refrigerant leak. This is due to the steel clamp causing corrosion in the aluminum pipe it holds for the A/C receiver/drier. The pipe can be replaced, although the leak can happen again if the pipe is not wrapped by vinyl tape before reintroducing the clamp.
A multitude of problems, big and small, besot fourth-generation Mazda 626s (1993 to 1997). The outer door handles are prone to come loose, A/C performance is generally mediocre, welds for wiper-arm support are fragile, speedometers tend to fail, mis-positioned radiator dampers cause steering wheel vibration, and transmission leaks can occur due to damaged torque-converter hub seals.
The biggest problem with fourth-generation Mazda 626s, however, are with the engine. Original motor mounts are fragile (Mazda offers redesigned replacements), and the engine can stall if there is a cracked mass-airflow snorkel tube. Also, the engine can produce a variance of sounds due to slippage between the exhaust-camshaft driven gear and friction gear, or carbon build-up in the combustion chamber.
The fifth and last generation (1998 to 2002) are the least problem-prone of the Mazda 626s. Vehicles with brake squeal can receive new rear brake shoes with revised lining material to curb it, and a redesigned block heater made of cast brass is available to stop coolant leaks. Also, Mazda has a redesigned bracket for noises made by the vapor-emission control valve. Some 1999 626s have faulty sunroofs, at which point the dealer can check for broken or missing panel-bumper clips, loose guides, or cable and motor problems.
For most of its run, the Mazda 626 was the car manufacturer's top seller. However, in terms of reliability (let alone popularity and sales), it fell short of its midsize competitors such as the Toyota Camry and Honda Accord.
