How to Replace the Fuel Cap on a 2020 Chevrolet Traverse (Fix EVAP & Check Engine Light)
Step-by-step fuel cap/capless system checks, required tools and parts, and tips to clear EVAP warnings
How to Replace the Fuel Cap on a 2020 Chevrolet Traverse (Fix EVAP & Check Engine Light)
Step-by-step fuel cap/capless system checks, required tools and parts, and tips to clear EVAP warnings
š§ Traverse - Fuel Cap Replacement
On your Traverse, replacing the fuel cap is usually a quick fix for a loose/damaged cap seal that can trigger a āCheck Engineā light or āTighten Fuel Capā message. Some Traverses use a capless fuel system (no screw-on cap), so Iāll show both pathsāpick the one that matches what you see at the fuel filler.
Difficulty Level: Beginner | Estimated Time: 0.1-0.3 hours
ā ļø Safety & Precautions
- š§Æ Work outdoors or in a well-ventilated area; fuel vapors are flammable.
- š No smoking, sparks, or open flames near the fuel door.
- š Turn the engine OFF before opening the fuel door.
- 𧤠Wear gloves; gasoline can irritate skin.
- š Battery disconnect is not required for this job.
š§ Required Tools
You'll need the following tools for this repair:
- Nitrile gloves
- Safety glasses
- Clean shop rag
- Flashlight
š© Required Parts
HowToo sells all the parts you need for this repair:
- Fuel filler cap (OE-style, tethered if equipped) - Qty: 1
š Before You Begin
- š æļø Park on level ground, shift to Park, and turn the engine OFF.
- ā½ Let the area cool if you were just driving (reduces vapor pressure).
- š Open the fuel door and confirm what you have: a screw-on cap or a capless flap.
šØ Step-by-Step Instructions
Follow these steps in order:
Step 1: Open the fuel door
- Open the fuel door by hand.
- Use a flashlight to look inside and confirm whether thereās a screw-on cap or a spring-loaded flap (capless).
Step 2A: If you have a screw-on fuel cap, remove it
- Turn the cap counterclockwise by hand until it comes off.
- Set it aside where it wonāt get dirt on it.
Step 3A: Inspect and clean the sealing surfaces
- Use a flashlight to inspect the capās rubber seal (often called an O-ring, which is a round rubber gasket that seals vapors).
- Wipe the cap seat and the filler neck rim with a clean shop rag.
- Clean and dry beats āextra tight.ā
Step 4A: Install the new fuel cap
- Thread the new cap on clockwise by hand.
- Tighten until it clicks (typically 1ā3 clicks). Do not use tools.
- If it has a tether, make sure the tether isnāt pinched and the cap hangs freely.
Step 2B: If you have a capless system, there is no cap to replace
- Use a flashlight to inspect the spring-loaded flap and the sealing area.
- Wipe the visible sealing surface with a clean shop rag.
- If youāre getting a āTighten Gas Capā style warning on a capless system, the usual causes are dirt on the seal, a damaged flap/seal, or an EVAP leak elsewhere (this would need diagnosis).
Step 5: Close the fuel door
- Close the fuel door firmly by hand until it latches.
ā After Repair
- š Drive normally; if a āCheck Engineā light was on due to a loose cap, it may take a few trips to turn off on its own.
- š If the light/message returns, the issue may be an EVAP leak (not always the cap). A scan for EVAP codes is the next step.
- š If you smell fuel near the door area after replacement, re-check that the cap is clicked tight and the seal area is clean.
š° DIY vs Shop Cost
Shop Cost: $50-$180 (parts + labor/diagnostic)
DIY Cost: $15-$45 (parts only)
You Save: $35-$135 by doing it yourself!
Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 0.2-0.5 hours.
šÆ Ready to get started?
HowToo makes it easy: same-day/2-day shipping on every part, plus all the tools and specialty tools you need! Check out the parts and tools sections below to add everything to your cart.

















