This sounds like a gnarly problem.... leaving the fuel cap off would
constitute a gross EVAP system leak and should trigger the CEL if left
unatended. At any rate, it will likely require some emissions systems
diagnostics to find the cause. I'd suggest having the PCM scanned for codes
and choosing the appropriate diagnostic routine for your findings.

FWIW... I see no mention of a fuel cap warning light in the WSM until
2002.... Perhaps your owners manual might shed some light on the subject.


"Kugar" > wrote in message
...
> On my Ford Explorer 2000 EB's dash board, the fuel cap warning light comes
> on
> when I start the engine then goes out (just as other warning lights on the
> dash)
>
> BUT, it does not turn on if the fuel cap is NOT capped back on the fuel
> inlet.
>
> During the last week twice I forgot to cap the fuel inlet after fueling,
> there
> was no warning light on the dash, I discovered my mistake after reaching
> the
> destination, about 50 miles of highway driving..
>
> Where is the sensor for this light and where should I start looking to
> return it
> to normal function ?
>
> Thanks in advance.
>
> Matt