How to Replace the Fuel Cap on a 2018 Dodge Challenger (Fix EVAP Leak & Check Engine Light)
Step-by-step fuel cap replacement with tools, part tips, safety precautions, and post-repair checks for 2008, 2009, 2010
How to Replace the Fuel Cap on a 2018 Dodge Challenger (Fix EVAP Leak & Check Engine Light)
Step-by-step fuel cap replacement with tools, part tips, safety precautions, and post-repair checks for 2008, 2009, 2010
đź”§ Challenger - Fuel Cap Replacement
Replacing the fuel cap on your Challenger is a quick job that helps prevent fuel vapor leaks and check-engine lights related to the EVAP system. You’ll remove the old cap from the filler neck and install a new one that seals correctly.
Difficulty Level: Beginner | Estimated Time: 0.1-0.2 hours
⚠️ Safety & Precautions
- ⚠️ Work in a well-ventilated area and keep away from sparks, cigarettes, or open flames.
- ⚠️ Do not replace the cap right after driving if you smell strong fuel vapors; let things cool down.
- ⚠️ No battery disconnect is required.
đź”§ Required Tools
You'll need the following tools for this repair:
- Nitrile gloves
- Clean shop towel
- Flashlight
🔩 Required Parts
HowToo sells all the parts you need for this repair:
- Fuel cap (OEM-style, sealed) - Qty: 1
đź“‹ Before You Begin
- Park on level ground, turn the engine off, and remove the key.
- Open the fuel door.
- Use a flashlight to check that the filler neck area is clean and dry.
🔨 Step-by-Step Instructions
Follow these steps in order:
Step 1: Remove the old fuel cap
- Put on nitrile gloves.
- Turn the fuel cap counterclockwise until it releases, then pull it off.
- If your cap is tethered (a small strap), let it hang safely so it doesn’t scratch paint.
Step 2: Inspect and clean the sealing surface
- Use a flashlight to look at the filler neck opening (where the cap seals).
- Wipe the sealing area with a clean shop towel to remove dust or grit.
- Clean seal = fewer EVAP leak codes.
Step 3: Install the new fuel cap
- Place the new cap onto the filler neck and turn it clockwise.
- Continue tightening until you feel/hear it click (if your replacement cap is a “click type”).
- Do not over-tighten past the clicks; the seal is made by the cap’s gasket.
Step 4: Close up and verify
- Close the fuel door.
- Use a flashlight to confirm the cap sits flat and straight (not cross-threaded).
âś… After Repair
- Start the engine and check that there’s no fuel smell around the fuel door.
- If you were replacing the cap due to a check-engine light, it may take a few drive cycles for the light to clear on its own; if it doesn’t, you’ll need an OBD2 scan to confirm the issue is resolved.
- If the cap was missing/loose, double-check it after your next fill-up.
đź’° DIY vs Shop Cost
Shop Cost: $30-$90 (parts + labor)
DIY Cost: $15-$40 (parts only)
You Save: $15-$50 by doing it yourself!
Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 0.2-0.4 hours.
🎯 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.
















