Most Subarus with a traditional fueling system use a standard gas cap that screws on and clicks when properly tightened. You can replace it with a genuine Subaru cap or a compatible aftermarket cap. Some newer or regional models use capless fueling, which has no cap to replace; in those cases, service steps differ.
Know what kind of fuel system your Subaru uses
Before proceeding, identify whether your model uses a traditional threaded gas cap or a capless fuel filler. The guidance below covers the traditional cap, which remains common in many Subaru models, while capless systems require a different approach typically handled by a dealer or qualified technician.
Replacing a traditional gas cap
If your Subaru has a conventional cap, follow these steps to replace it safely and effectively.
Cost and time considerations
Replacing a standard gas cap is usually inexpensive and quick. Most shoppers can complete the task in about 10–15 minutes, whether at home or a shop. Genuine Subaru caps are widely available, and many reputable aftermarket caps are compatible when they match the thread pattern and venting requirements.
- Buy the correct replacement gas cap for your model year and trim. Check the owner's manual, Subaru parts catalog, or ask a dealer or parts retailer to confirm compatibility.
- Open the fuel door and locate the gas cap threaded onto the filler neck.
- Unscrew the old cap by turning it counterclockwise until it comes off. If the cap is locking, you may need to press the release or use the key fob if your model includes a locking feature.
- Inspect the gasket or seal on the old cap and inspect the filler neck for damage, dirt, or debris. If the seal appears cracked or the neck is damaged, replace the cap assembly or seek professional service.
- Install the new cap by threading it clockwise onto the filler neck. Tighten it until it seats, then give it a additional gentle snug turn. Many caps will click once or twice to indicate a proper seal.
- Close the fuel door and start the vehicle if needed. Drive normally; if the fuel-cap warning light was on, it should reset after a few drive cycles. If it remains lit, have the system checked for leaks or gasket issues.
With the new cap in place, ensure the seal is intact and the fuel system is reported as secure by the vehicle’s evaporative system.
Capless fueling: what to know
Some Subaru models use capless fueling, which eliminates the traditional cap entirely. In these cases, there is no gas cap to replace. If you experience a problem with a capless system—such as a stubborn filler neck, sensor issue, or EVAP warning—consult the owner’s manual or a Subaru dealer for the correct diagnostic and replacement path, which may involve the filler neck assembly or related valves rather than a cap.
Where to buy a replacement
Replacement gas caps can be sourced from multiple outlets. Make sure you buy the right part for your exact model year and configuration, and choose between genuine Subaru parts or compatible aftermarket options.
- Subaru authorized parts department or dealership
- Major auto parts stores and online retailers with Subaru-compatible caps
- Automechanic or service centers that stock OEM or aftermarket caps
Choosing the correct part helps maintain warranty coverage and ensures proper venting and fitment for the EVAP system.
What to do if the check engine light stays on
If the check engine light (MIL) remains on after replacing the cap, the issue could be a poor seal, a damaged gasket, a cracked filler neck, or another EVAP system fault. Recheck the installed cap for proper threading and seal, and consider having the fuel system scanned with an OBD-II reader to identify leaks or codes that point to the EVAP circuit. Persistent warnings should be evaluated by a professional technician.
Summary
For most Subaru owners, replacing a traditional gas cap is a simple, quick maintenance task: obtain a compatible cap, remove the old one, install the new cap until it clicks, and drive to ensure the EVAP system recognizes the seal. If your model uses capless fueling, there is no cap to replace and you should consult the manual or a dealer for guidance. In all cases, verify compatibility, keep the filler area clean, and seek professional help if warning lights persist after replacement.