What does this code mean?


I have a 1999 Ford Taurus, and the “Service Engine Soon” light has been on for about a month. Finally went to Auto Zone for a diagnostic and the code came up as:

P0442 and “evap system leak - small”.

I replaced the gas cap but the light is still on.

A friend suggested disconnecting the battery to reset the light. Is that a good idea?


It takes some specialized equipment, and know how to diagnose the nasty P0442. Your best bet is to take it in, but if I where to take a stab in the dark I would guess the fuel filler neck.
Good Luck


To answer your question, disconnecting the battery for about 15 min should clear the code


Thank you.
And if the light comes back after, what about the fuel filler neck? Do they rust out? Get damaged? Need replacement? Are they expensive to fix? (I’m not panicking - really.)


I’m guessing the fuel neck is maybe $100.00 to $150.00, but there is a lot of other possibilities, thats why I suggest taking it in.


O.K. and thank you.

the Nana


The filler neck can rust out if you live in a place that uses a lot of road salt. Water can pool by the door, salt splashes up and settles there and in a few years you can have a pin hole leak. Spend three minutes looking around. If you see a rusted spot buy some JB weld epoxy for $4, mix up a little and slather it over the hole. You’ll be good to go for another two years.
It can also mean a dried out or cracked hose to the carbon canister. That’s another three minutes fix only this time you’ll need duct tape.


Did Auto Zone reset your CEL and it came back on? If so then you need to check all vacuum lines in your EVAP system. I would also check to see if your EVAP canister vent valve and EVAP canister purge valve are working properly. I had this same code on my 96 mustang with the 3.8 liter engine and it turned out to be both the EVAP canister vent valve and EVAP canister purge valve.