On my way to work this morning I received a Check Fuel Cap light. So I checked it; looks fine. Took it off, looked at it, put it back on, restarted truck. Light still on....

Do I need a new cap?

 

Fuel caps fail because the O-ring that seals them
breaks. Check to see if the O-ring is missing; if so
then that's the problem.

If the cap is indeed OK, then the leak may be
somewhere else, like around the filler hose for
instance. Try tightening up the clamps......

 

disconnect the battery for 15 minutes and hook it back up. if the code doesn't come back leave it lol i had the same issue a month ago and it hasn't come back on

 

For sure, thanks.

Didn't think gas caps went bad.

 

when mine went on it was from a vent hose getting disconnected. the connection (or disconnection in my case) can be found by looking in the drivers side front wheel well behind the rubber flap things.

 

Bought a new cap, all is well, so far.

 

I had that same problem and bought an OEM fuel cap. The light stayed on, so I started checking the rest of the fuel system. Finally I found that the vacuum line for the charcoal canister purge valve had disconnected. I plugged it back up and the light went away. The purge valve is located on the driver's side of the engine bay, near the ABS stuff.

 

Damn light just came back on. Check fuel cap wtf. It's brand new...

I'll take a look at the charcoal canister purge valve

 

When there is a large leak in the evap system, the Check Cap light comes on first to alert the driver to a possible loose cap before lighting the Check Engine Light and setting an OBDII trouble code.

Since you seem to have eliminated the cap, it's time to look elsewhere. If you have a body lift, the first place to check is at the filler hose and vent extensions.

 

Thanks for the reply Bob.

I took a closer look. Made sure everything was tight by the fuel cap, then checked the canister. Seems one of the hoses came loose somehow. Plugged it back in, reset the battery and light is off, for now...

If it comes back on I'll let you know.

 

That could do it.

 

I replaced the cap on my 01 a few years back because I was always getting a leak code. I always cleard it as I knew it was the cap. One day the cap just wouldn't come off and I needed to replace it. Ever since I replaced it, no issues. The OE replacements are just a couple bucks, so it wouldn't hurt to just replace it and see what happends.