I need help.
My 1998 mazda b4000 repeatedly sets a code indicating massive evaporative emission
Control leak.I have replaced the gas cap.and the hose from the check valve assy.to
The throttle body.It resets the code about every three days.
Does this system have a charcoal canister?I went a local ford dealer and they could not
Locate it.

Can you tell me the massive code
I can look it up
P0442 is quite common
P0446 also

Can you tell me the massive code
I can look it up
P0442 is quite common
P0446 also

The scan code is P0455
Definition : EVAP large leak detected.

Thanks for the reply
Don

The scan code is P0455
Definition : EVAP large leak detected.

Thanks for the reply
Don
P0455 is comomonly referred to as "the gas cap code"
When the Evap system attempts to draw collected vapors from the canister, the vacuum necessary cannot be achieved because of a poor seal at the fuel fill cap.

I'd recommend a new gas cap and drive the car. The light will go out by itself or you can take it to have the light turned off

I replaced the gas cap first thing.It is an after market part not from ford/mazda though.
I cleared the code and it reset three days later.Every time I have reset it ,it reappears at appoximately the same time {morning}on the third day on my way to work.I drive thirteen miles and it sets about 3/4s of the way there.
Seems strange but true.