Subaru Impreza Engine Replacement in Phoenix

The Impreza spans a wider engine range than most vehicles here. Naturally aspirated cars used EJ-series engines and later the FB20; WRX models used turbocharged EJ255 units; STI models used the EJ257.

A separate stream of demand comes from buyers wanting JDM EJ20 engines, the EJ205 and the STI EJ207, which were never fitted to US-market Imprezas. Those are swaps with engine-management work attached, not replacements.

The practical effect is that "Impreza engine" is not a request anyone can act on. The model, the year and whether the car is a WRX or an STI all change the answer.

WRX and STI are not the same order

The WRX uses the EJ255 and the STI the EJ257. They are both turbocharged 2.5-litre boxers and they are not interchangeable. On a car that may have been modified, the badge is weaker evidence than the stamp.

Separately, there is steady demand for JDM EJ20 engines, the EJ205 and the STI EJ207, which were never fitted to US-market cars. Those are swaps with engine-management work attached. If the goal is simply to get the car running again, the matching EJ25 variant is the direct route.

Where Subaru Impreza orders go wrong

• WRX and STI use different turbocharged engines; they are not interchangeable.
• JDM EJ20 units are a swap, not a replacement, on a US-market car.
• Later naturally aspirated cars use the FB20, a different engine from the EJ family.
• Turbocharged builds need fuel system, intercooling and engine management planned together.

None of this needs to be worked out on your own. The Engine Finder asks for the year, model and trim and does the identification from there. The engine code field is optional precisely because most people do not have it.