A genuine rally-bred performance icon — exciting, capable, and carrying an engine whose documented tuning sensitivity makes modification history the single most important factor in any purchase decision.
The STI's rally-bred all-wheel-drive chassis was genuinely developed around this turbocharged engine's character, and the pairing remains exceptional today — a large part of why this generation has such a strong, enduring enthusiast following.
Because this is a specialist performance car, the used population includes an unusually high proportion of modified, tracked, or rallied examples — the engine page's tuning-history checklist matters more here than on almost any daily-driver car.
This is about the car itself — for engine-specific failure points, see the dedicated engine page below.
This WRX STI is a defining application of the EJ257. The tuning-history checklist on the dedicated engine page should be treated as essential before buying.
FULL ENGINE BREAKDOWNSubaru 2.5L Turbo (EJ257) — Reliable or Not →This is the single most important step on any WRX STI: ask directly whether the car has been tuned, and get the tuning file and any supporting documentation.
Have a specialist perform a compression or leak-down test to check for early ringland-related symptoms, especially on modified examples.
Check for a sweet coolant smell or visible seep near the lower edge of the cylinder head, the head gasket symptom shared with the naturally aspirated EJ25.