Gas cap
 

Hey guys will an auto zone gas cap work for my 89 vert, or, like a thermostat, am I better off with OEM?

if you do not have emissions then an aftermarket one should be fine. if you have emissions you might just want to stick with OEM.

If you have access to a junkyard, many Mazda caps will interchange.
Some even have handy retaining straps, so you can upgrade and maintain OEM respectability at the same time.

Car is stock so OEM is best I suppose. What other Mazdas have proper caps?

FC has its own cap, if you're going OEM. FC01-42-250 is the Mazda number, its ~$20

I'm curious, anything in particular that you recall which has a strap? I've always thought of retrofitting a strapped cap, just low on the to-do list.

Mine came from a 626.

I have a Gates 31613

Would a missing or wrong gas cap cause a ck engine light? I just got the car and haven't had a chance to run the codes.

These cars i doubt it, newer ones, yes

The gas cap will not cause a code until you reach enhanced OBD2, which is after 1996

no, but a bad cap will fail a basic pressure test which is still a step used in most modern state emissions testing.

nevada and california both tested my caps with EVERY smog test.

even on post OBDII cars it is usually added as a secondary test measure in case the system is not registering a leak, i saw plenty of smog tests check the cap even on late model cars.

Good info thanks guys!

They dont do any of that here anymore if it can't be plugged in its safety inspection only. Cheap too.

Tennessee is likely the same, but i don't know, and why i treated the answer as worst case/generic. if he still even lives there, plenty of people move and forget to update location.

No emissions testing here in TN.

In case anyone comes here looking for emissions help, I just passed CA smog with a generic parts store cap. So functionally, it is OEM or better.

And yes, I know....nobody else cares.

Hey I care! Dealer ordered cap, I couldnt wait, got one at advance auto. Works fine.