Is the Subaru Impreza engine reliable?
The current generation of Impreza models with the 2.0-liter FB20 engine is generally reliable when maintained properly; older Impreza models that used the EJ-series 2.5-liter engine are more prone to head-gasket failures and related repairs. Reliability varies by generation and by how well the vehicle has been cared for.
Engine evolution and reliability at a glance
The Impreza has progressed through several engine families since its debut. Early cars relied on the EJ-series 2.0L and 2.5L engines, while the modern lineup uses the FB-series 2.0L across most trims. This shift reduced some recurring failure modes and generally improved long-term reliability, though no engine is immune to wear and tear.
- EJ-series engines (older models): Commonly found in pre-2011 Impreza models, including 2.0L and 2.5L variants. The 2.5L in particular is well known for head-gasket failures as mileage climbs or after cooling-system issues, which can lead to costly repair bills if not addressed promptly.
- FB-series engines (modern models, starting around 2012): The 2.0L flat-four used in most current Imprezas is praised for robust design and a timing chain, reducing some maintenance demands. Occasional reports of oil consumption in a minority of early FB20 units exist, but overall reliability is considered solid with regular service intervals.
Overall, reliability has improved with the FB-series, but a well-documented maintenance history remains crucial for long-term peace of mind.
Reliability by engine family
EJ-series reliability snapshot
The EJ-series powered many earlier Impreza generations. While durable in many scenarios, the 2.5L variants earned a reputation for gasket-related failures and overheating if cooling components were neglected. Regular cooling-system maintenance and timely repairs can mitigate the risk, but when head-gasket work is needed, cost and downtime can be substantial.
- 2.5L EJ engines: Higher risk of head-gasket leaks with age or overheating; maintenance history strongly influences outcomes.
- 2.0L EJ engines: Generally dependable, but age and mileage can bring typical wear items and leaks; attentive upkeep helps maintain reliability.
In summary, EJ-powered Imprezas can offer reliable performance with disciplined maintenance, but head-gasket risk makes their used-car prognosis more variable.
FB-series reliability snapshot
The FB-series 2.0L, introduced in mid-2010s Imprezas, is widely regarded as the more reliable option in the lineup thanks to design updates, a timing chain, and improved efficiency. Some early FB20s have been associated with oil consumption in a minority of cases, and some model years saw recalls or service bulletins related to emissions and ancillary systems, but overall these engines tend to be durable with routine maintenance.
- FB20 2.0L: Strong reliability record when serviced per schedule; timing chain reduces major maintenance events compared with belt-driven designs.
- Oil consumption and minor recalls: Occasional reports exist for certain years; staying current with dealer service notices helps mitigate risk.
For most buyers, the FB-series engines in Imprezas offer a more predictable reliability profile than older EJ 2.5L units, provided maintenance is consistent.
Used-car shopping: what to check for engine reliability
When evaluating a used Impreza, a careful pre-purchase check can reveal potential reliability concerns and help avoid costly surprises down the line.
- Verify engine history and significant repairs: Look for records of cooling-system work and any head-gasket service, especially on 2.5L models from the EJ era.
- Test for oil consumption: A quick burn test over a few hundred miles can indicate abnormal consumption, which warrants deeper inspection.
- Compression and leak-down testing: These tests help assess overall engine health beyond surface symptoms.
- Inspect for leaks and signs of overheating: Look around the valve covers, timing area, and cylinder head gaskets for oil or coolant leaks.
- Check for recalls and service campaigns: VIN-based recalls or updates can address known reliability concerns.
A thorough inspection, ideally by a qualified technician, plus a complete maintenance and recall history, greatly improves confidence in the engine’s long-term reliability.
Maintenance practices to maximize reliability
Proactive maintenance is the best defense against reliability issues in any Impreza engine family.
- Follow the manufacturer’s schedule for oil changes and use the recommended synthetic oil (often 0W-20) and filter; stay within those intervals even in varying climates.
- Replace spark plugs at the recommended intervals to maintain combustion efficiency and avoid misfires that can mask other issues.
- Keep cooling system components in good order: coolant flushes, hose inspection, and water-pump checks help prevent overheating that can damage head gaskets on older engines.
- Monitor oil consumption and address any increases promptly with diagnostics and dealer guidance.
- For CVT-equipped models, adhere to the CVT fluid maintenance schedule and address any transmission symptoms that could be mistaken for engine trouble.
With disciplined maintenance, Impreza engines—both older EJ and newer FB-series—tend to deliver reliable performance over many miles.
What owner reviews and independent testing show
Independent testing and owner surveys generally position Subaru reliability as solid to favorable, with some year-to-year variation. The newer FB20-powered Imprezas tend to be rated more reliably than the older EJ25-based versions, largely due to improved cooling, oil control, and reduced head-gasket risk. However, reliability can be strongly influenced by maintenance history, accident history, and whether recall work and service bulletins were completed.
In practice, buyers should weigh the engine history, service records, and any documented head-gasket or oil-consumption issues on a per-model-year basis, then align expectations with maintenance discipline and the vehicle’s current condition.
Bottom line
In summary, the Subaru Impreza’s reliability is strongest in the modern, FB20-powered models when they are properly maintained. Older EJ-series engines—particularly the 2.5L—carry a higher risk of head-gasket-related repairs and related costs. For prospective buyers, a careful pre-purchase inspection, verified service history, and adherence to maintenance schedules are the best ways to ensure long-term engine reliability.
Summary
The Impreza’s reliability story is generation-dependent. Modern FB20 engines offer solid reliability with routine maintenance, while older EJ-powered variants—especially the 2.5L—are more prone to gasket failures and related issues. A well-documented maintenance history and a thorough pre-purchase check are essential for anyone considering a used Impreza, and ongoing, proactive maintenance remains the key to long-term engine health.
