Buying Guide / 2000 - 2014
Subaru Impreza WRX & STI
Rally-bred, turbo flat-four, symmetrical AWD. The Impreza defined a generation of performance cars, but the EJ engine has weaknesses every buyer needs to understand.
Rally-bred, turbo flat-four, symmetrical AWD. The Impreza defined a generation of performance cars, but the EJ engine has weaknesses every buyer needs to understand.
The Impreza WRX and STI put rally-winning technology on the road. Prices have risen sharply, but the EJ flat-four engine carries well-documented risks that can turn ownership into a costly exercise if ignored.
We've compiled 14 known issues for the Impreza WRX and STI in our database. Here are the five that matter most, drawn from data by Subaru specialists and owner communities across the UK.
Go deeper: Run a free Carwise report on a specific Impreza to see which issues apply to that exact car, plus full MOT history, mileage checks and a personalised buyer checklist.
The EJ flat-four engine is notorious for head gasket failures. The boxer layout means gravity pulls coolant and oil away from the gasket surfaces. Symptoms include overheating, white smoke, mayonnaise-like substance under the oil cap, and coolant loss.
Look under the oil cap for emulsion. Check coolant level and look for staining around the head gasket area. A compression test is recommended before purchase.
The pistons can crack at the ringland (the land between piston rings), particularly on tuned cars or those running high boost. Detonation from poor fuel quality or aggressive maps is the usual cause.
Ask about tuning history and fuel used. Blue smoke under hard acceleration is a warning sign. A leakdown test is the definitive check for ringland condition.
The turbo bearings can wear, especially on cars with delayed oil changes or those that have been switched off without a cool-down period. Oil starvation and heat soak are the main causes.
Listen for turbo whine or bearing noise on boost. Blue smoke on overrun indicates oil passing through the turbo seals. Check oil change intervals in service history.
The 5-speed gearbox in the WRX is the weak point. Synchros on 2nd and 3rd gear wear, especially on cars that have been launched hard or track day'd. The STI 6-speed is significantly stronger but not immune.
Test all gears from cold. Crunching into 2nd or 3rd is a common finding. A smooth, precise shift across all gears from cold is what you want to feel.
Subaru bodywork was not well-protected from the factory. Rear wheel arches, sills, and the underside of the boot floor are common rust areas. UK-registered cars from new are generally better than late JDM imports.
Inspect rear arches carefully, check sills behind plastic covers, look under the boot carpet. Surface rust may hide more serious structural corrosion underneath.
The Impreza WRX and STI defined a generation of performance car fans. The combination of turbo flat-four, symmetrical AWD, and rally heritage creates a driving experience nothing else matches. The mechanical issues are well-documented and parts availability remains strong through the enthusiast network.
STI models with the 6-speed gearbox are the stronger buy mechanically. The key is finding a car that has been maintained properly and not thrashed by a succession of owners chasing power figures. Service history and a conservative modification philosophy are worth more than any spec sheet.
Enter the registration for MOT history, mileage verification, known faults for that exact variant, and a Carwise Score.
Check a vehicle nowCompiled from independent expert sources, specialist workshops and our database of 14 known Impreza WRX/STI issues. We are not affiliated with any source listed.
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