How to Replace the Fuel Cap on a 2020-2023 Jeep Gladiator (Fix EVAP Leak & Check Engine Light) (Engine: V6 3.6L)
Step-by-step instructions with required tools/parts, safety tips, and what to do if the CEL returns
How to Replace the Fuel Cap on a 2020-2023 Jeep Gladiator (Fix EVAP Leak & Check Engine Light) (Engine: V6 3.6L)
Step-by-step instructions with required tools/parts, safety tips, and what to do if the CEL returns for 2020, 2021, 2022, 2023
š§ Gladiator - Fuel Cap Replacement
Replacing the fuel cap on your Gladiator is a quick job: you remove the old cap and install a new one that seals correctly. A good seal helps prevent fuel vapor leaks, check-engine lights, and fuel smell.
Difficulty Level: Beginner | Estimated Time: 0.1-0.2 hours
ā ļø Safety & Precautions
- ā ļø Work outside or in a well-ventilated area away from flames or smoking.
- ā ļø Turn the engine OFF before opening the fuel door.
- ā ļø If you smell strong fuel, stop and let vapors clear.
- ā ļø No battery disconnect is required for this repair.
š§ Required Tools
You'll need the following tools for this repair:
- Nitrile gloves
- Clean shop towel
- Plastic trim tool (specialty)
- Flashlight
š© Required Parts
HowToo sells all the parts you need for this repair:
- Fuel filler cap (gas cap) for Gladiator - Qty: 1
š Before You Begin
- Park on level ground and shut the engine off.
- Let the truck sit 1-2 minutes if you just drove it.
- Open the fuel door and wipe around the filler opening with a clean shop towel.
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 for dirt or damage around the filler neck (the metal tube you fuel through).
Step 2: Remove the old fuel cap
- Turn the cap counterclockwise by hand until it releases.
- If your cap has a tether (the small strap that keeps it from getting lost), let it hang without twisting it.
- If itās stuck, turn slowly and steadily.
Step 3: Inspect and clean the sealing area
- Use a clean shop towel to wipe the sealing surface on the filler neck (the smooth ring the cap seals against).
- Look at the old capās rubber seal (the gasket). If itās cracked, flattened, or missing, that can cause an EVAP leak and a check-engine light.
Step 4: Transfer the tether (if required)
- If the new cap does not include a tether and your old cap uses one, move it over carefully.
- Use a plastic trim tool (specialty) to gently pry the tether clip loose if itās clipped to the cap. (A plastic trim tool is a non-metal pry tool that helps prevent scratches.)
- Do not use a metal screwdriver hereāit's easy to damage the plastic.
Step 5: Install the new fuel cap
- Thread the new cap on by hand, turning clockwise.
- Tighten until you feel it fully seat; if itās a ratcheting-style cap, keep turning until it clicks a few times.
- Start threads gently to avoid cross-threading.
Step 6: Close the fuel door
- Close the fuel door firmly by hand.
- Use a flashlight to confirm the cap is seated and the tether (if equipped) isnāt pinched.
ā After Repair
- Start the engine and verify thereās no fuel smell around the fuel door.
- If you had a check-engine light for a loose cap, it may take a few drive cycles to clear on its own.
- If the light stays on, youāll likely need the code readāan EVAP leak can have other causes besides the cap.
š° DIY vs Shop Cost
Shop Cost: $40-$120 (parts + labor)
DIY Cost: $15-$45 (parts only)
You Save: $25-$75 by doing it yourself!
Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 0.1-0.2 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.
Guide for Fuel Tank Cap replace for these Jeep vehicles
| Year Make Model | Sub Model | Engine | Body Style |
|---|---|---|---|
| 2023 Jeep Gladiator | - | V6 3.6L | - |
| 2023 Jeep Gladiator | - | V6 3.0L | - |
| 2022 Jeep Gladiator | - | V6 3.6L | - |
| 2022 Jeep Gladiator | - | V6 3.0L | - |
| 2021 Jeep Gladiator | - | V6 3.6L | - |
| 2021 Jeep Gladiator | - | V6 3.0L | - |
| 2020 Jeep Gladiator | - | V6 3.6L | - |

















