Emissions Requirements

[JadeEmperor]

Wondering if anyone knows the specifics on emissions requirements. Specifically the "Gas Cap Test" requirement. At least in AZ they do exhaust check on anything newer then '66, and they also do a gas cap check. I'm just not sure what that is.

I know on my newer vehicles they do some sort of pressure thing, clamp a line and put some cap with vacuum lines where the regular cap goes to check for system leaks.

I'm thinking on the older stuff they only want to see a cap, that it can be removed and the seal is not cracked (i.e. bad rubber).

to the nuts and bolts - the reason I am asking is that I did a custom tank install (spare tank area) with a fuel fill neck utilizing a vented gas cap that is for use on motorcycles. I don't know that motorcycles go through the same requirements. (should have thought of that sooner) Anyways, the cap has a rubber o-ring, I built the neck with a vent that goes to the tank, etc.

Anyone see any issues or should I just take it through and see if I pass.

Thanks in advance for helping calm my nerves.

I'll post pics of the install soon.

[Longhorn Man]

I'm pretty sure the 70 would have a vented cap stock.

[walker]

Worst thing that will happen is they will make you come back with a new gas cap.

[Hooter]

shouldnt all tanks have a vented cap, otherwise how would the air get into the tank, I remember I had a unvented cap on my 74 Cheyenne once without knowing, and the tank was imploding and my truck would stall