Same low-tension ring issue as the Forester FB25 — affects 2012-2016 Imprezas.
Reviewed by SubaruReview Editorial Team · Last reviewed 2026-05-10 · Editorial standards
This is one of several documented Impreza problems we track, and it fits inside the broader Engine Guides guide. If you're weighing repair against replacement, cross-check the Subaru repair-cost database and any open NHTSA recalls on your VIN before booking a shop.
Low-tension oil control rings lose seal; oil migrates past and burns.
Low-tension ring design.
Low-tension ring design.
National average $0–$3,800. $0 if within Yaeger class-action coverage window; $2,300-$3,800 out of pocket for piston-ring / short-block replacement.
Difficulty 2/5. Short-block replacement
1 quart per 1,000-1,500 miles; Plug fouling
Owners typically pay $0–$3,800 at an independent Subaru shop, parts and labor included. Our Subaru Head Gasket Replacement Cost guide breaks the job down by parts, labor hours, and where the money actually goes.
We rate it 2/5 on our DIY scale. Confident wrenchers can tackle it in a weekend using the permanent-fix steps above. Cross-reference the reliability & common problems hub for related jobs worth bundling while you're in there.
It's part of our Engine Guides cluster, which collects every article covering the same system as this failure.
Same failure mechanism documented on a different Subaru — shares components with this article.
Same failure mechanism documented on a different Subaru — shares components with this article.
EJ, FA, FB, and EZ boxer deep-dives — the engine background this failure sits inside.
Dig into the Problems Database to plan your next maintenance sprint, or browse every model hub for buyer's guides, generation breakdowns, and known-issue lists.