"Check Fuel Cap" I know what needs to be fixed, but...

[Huntsman06]

So my gen 3 has had the "Check Fuel Cap" light on and off a few times, but each time it I would get out, remove and reattach the cap, and then after driving 4 or 5 miles the light would turn itself off. Well, this last time that worked as usual but 3 days later the check engine light is on. I had the code read (p0442, only 1 code) and it continually suggests that the check engine light is mad that I never properly fixed the fuel cap. What's odd is that the fuel cap light has NOT come back on even once since the check engine light came on.

I'm going to buy a replacement cap anyway (the little wire attaching it to the car is broken as it is) but I wanted to confirm that my problem sounds like the typical case. Does the "Check Fuel Cap" light usually stay on until the check engine comes on or is it strange for the fuel cap light to come and go like mine is?

 

[imp]

So my gen 3 has had the "Check Fuel Cap" light on and off a few times, but each time it I would get out, remove and reattach the cap, and then after driving 4 or 5 miles the light would turn itself off. Well, this last time that worked as usual but 3 days later the check engine light is on. I had the code read (p0442, only 1 code) and it continually suggests that the check engine light is mad that I never properly fixed the fuel cap. What's odd is that the fuel cap light has NOT come back on even once since the check engine light came on.

I'm going to buy a replacement cap anyway (the little wire attaching it to the car is broken as it is) but I wanted to confirm that my problem sounds like the typical case. Does the "Check Fuel Cap" light usually stay on until the check engine comes on or is it strange for the fuel cap light to come and go like mine is?

@Huntsman06
The fuel cap check valve, built-in, must maintain a certain minimum vapor pressure level in the tank. A pressure sensor continuously monitors that. If the check valve leaks, fuel vapors are escaping into the atmosphere, a form of air pollution. Replacing the cap will likely resolve the problem. imp

 

[rocco123]

Very likely the fuel filler neck rusted thru.
That's funny "check fuel cap light"