How to Replace the Fuel Cap on a 2016 Ford F-150 (Fix EVAP Leak & Check Engine Light)
Step-by-step install tips for standard vs. Easy Fuel capless systems, plus parts, tools, and safety checks
How to Replace the Fuel Cap on a 2016 Ford F-150 (Fix EVAP Leak & Check Engine Light)
Step-by-step install tips for standard vs. Easy Fuel capless systems, plus parts, tools, and safety checks
🔧 F-150 - Fuel Cap Replacement
Replacing the fuel cap is a quick job that helps prevent fuel vapors from leaking out of the tank. A loose, missing, or bad cap can trigger an EVAP warning and sometimes a check engine light.
Difficulty Level: Beginner | Estimated Time: 0.1-0.2 hours
⚠️ Safety & Precautions
- ⚠️ Work outdoors or in a well-ventilated area—fuel vapors are flammable.
- ⚠️ Turn the engine OFF and keep sparks/flames away from the fuel door.
- ⚠️ Don’t top off the tank after the pump clicks off.
- Battery disconnect is not required.
🔧 Required Tools
You'll need the following tools for this repair:
- Nitrile gloves
- Safety glasses
- Clean shop towel
🔩 Required Parts
HowToo sells all the parts you need for this repair:
- Fuel filler cap - Qty: 1
📋 Before You Begin
- Park on level ground and shift to Park.
- Turn the engine off and wait 1–2 minutes before opening the fuel door.
- Wipe dirt away before opening the filler.
🔨 Step-by-Step Instructions
Follow these steps in order:
Step 1: Open the fuel door
- Open the fuel door by hand.
- Use a clean shop towel to wipe dust/grit from around the filler area.
Step 2: Identify which filler system you have
- If you see a twist-on cap: follow Steps 3–4.
- If you see a spring-loaded flap with no cap (Ford “Easy Fuel” capless): follow Steps 5–6.
Step 3: Remove the old fuel cap (if equipped)
- Put on nitrile gloves.
- Turn the cap counterclockwise until it comes free.
- If it’s tethered (attached by a strap), let it hang and inspect the strap for cracks.
Step 4: Install the new fuel cap (if equipped)
- Thread the new cap on by hand (clockwise) until it’s seated.
- Keep turning until it clicks (usually 1–3 clicks). Those clicks mean it’s sealed.
- Use the clean shop towel to wipe the cap sealing area if you see dirt.
Step 5: If your A4 is capless (Easy Fuel), install the correct “cap”
- If you purchased a “fuel cap” because yours is missing, your F-150 may actually use a capless filler and may not need a traditional cap.
- What you may need instead is the correct replacement capless filler plug/cover (a protective plug some trims/aftermarket kits use) or repair parts for the capless neck.
- Use a clean shop towel to wipe the area and ensure the spring-loaded flap closes fully on its own.
- Don’t pry the flap with tools.
Step 6: Close the fuel door
- Close the fuel door firmly by hand.
- Wipe any spilled fuel immediately using a clean shop towel.
✅ After Repair
- Start the engine and confirm there’s no fuel smell near the fuel door.
- If you had a check engine light for an EVAP leak, it may take a few drive cycles to clear after the new cap is installed.
- If the light stays on, the issue may be the EVAP system (purge valve, vent valve, hoses), not the cap.
💰 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.
🎯 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.
















