Pre-Purchase Inspection Checklist

2018 Subaru WRX pre-purchase inspection checklist

What to check before you buy, built from NHTSA recall data, owner-reported failures, and mechanic intel. Print it or bring it to your mechanic.

Pre-purchase inspection · 2018 Subaru WRX
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2018 Subaru WRX
Base / Premium / Limited (4th gen VA, 2015–2021)
Monitor

The WRX is a highly capable performance compact — when stock and maintained. The critical risk on used examples is modification history: staged tunes, intake/exhaust without a tune, or high-boost maps significantly increase ringland failure risk on the FA20DIT. A stock WRX with regular Subaru-specified oil changes is reliable. A tuned or modified example is a significant gamble. Walk away from any WRX with an aftermarket intake, ECU tune, or missing service records.

Items to check
15
Open recalls
2
NHTSA complaints
290
Top concern
Engine (modified units)

Modification Check — Most Important

Aftermarket intake or exhaust

Critical — Walk Away
An aftermarket cold-air intake without a matching ECU tune runs the engine lean under boost. This is a leading cause of FA20DIT ringland failure. Even a returned-to-stock car may have already suffered damage.
Inspect intake box: if aftermarket (cone filter, no airbox) = walk away unless full stock restoration AND compression test is clean.
Est. cost: $3,000–$6,000 engine rebuild on ringland failure Source: Subaru FA20DIT modification risk / WRX community knowledge

ECU tune or Access Port

Critical — Walk Away
An Access Port in the OBD port or dealer datalog showing flash events = the car has been tuned. Stage 2+ maps significantly increase stress on pistons.
Check OBD-II port for dongles. Ask seller directly. Request datalog if possible.
Est. cost: $3,000–$6,000 if engine failure follows Source: Subaru WRX enthusiast community / Cobb Accessport records

Engine Health

FA20DIT compression + leakdown test

High Risk — Test Before Buying
On any used WRX, a compression and leakdown test is the best way to assess ringland health before purchase. Low compression (below 160 psi) or high leakdown (>15%) indicates internal wear.
Request or arrange a compression/leakdown test. Any cylinder below 150 psi or >15% leakdown = negotiate hard or walk.
Est. cost: $100–$150 test at a shop Source: Subaru WRX buyer standard

Oil consumption check

Monitor
The FA20DIT can consume oil, especially on high-revving examples. Check dipstick at viewing.
Check dipstick. Any consumption over 1 qt per 2,000 miles = investigate further.
Est. cost: $0–$2,000 Source: Subaru FA20DIT pattern

Piston ringland condition — listen for knock

High Risk
A failing ringland sounds like a rod knock — rhythmic metallic knock at idle that gets louder under load.
Listen at idle and under light load. Any knock = do not purchase.
Est. cost: $3,000–$6,000 engine work Source: Subaru FA20DIT ringland failure pattern

Drivetrain

6-speed manual vs CVT

Low Risk (manual) / Monitor (CVT)
The 6MT is the preferred choice for longevity. The Lineartronic CVT on the base model can fail at high mileage; replacement is $3,500+. Manual: check clutch engagement height.
Manual: test clutch at all speeds. CVT: check for any shudder or whining under acceleration.
Est. cost: CVT replacement $3,500–$5,000 Source: Subaru CVT replacement history

Rear differential fluid (AWD)

Low Risk
AWD differential and transfer case fluids should be changed every 25k miles.
Confirm differential service in records. Request service if unknown.
Est. cost: $200–$300 full drivetrain service Source: Subaru AWD service interval

Documentation

Oil change frequency — every 3,750 miles

High Risk
Subaru specifies 6,000-mile oil changes but WRX owners widely use 3,750 miles for turbocharged applications. Any WRX with 7,500-mile oil change intervals has elevated ring/bearing risk.
Request all oil change records. No documentation on a WRX = high risk premium.
Est. cost: n/a Source: Subaru turbo maintenance community standard

NHTSA Recalls (verify completion via VIN)

Multiple
Severity: Varies
Campaigns vary by build date — run the VIN at nhtsa.gov/recalls and require every open campaign closed before purchase. Remedy: Dealer remedy at no cost where a campaign applies.
After you buy: common DIY repair guides
Planning the upkeep this car will need? Our step-by-step guides cover oil changes, brake pads & rotors, battery replacement, transmission fluid, coolant flushes, and spark plugs — each with the tools, parts, torque specs, and common mistakes that matter. Browse all repair guides →

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