99 Sable gas cap
#1
99 Sable gas cap
Is there supposed to be an O ring on this gas cap? Computer codes indicate the system isn't keeping pressure.. There is a slot around the neck of the cap that an O ring would fit into..
#2
They will most likely have a inpregnated seal, meaning it is built into the cap. If you suspect leak, buy a new cap. If that does not solve the issue, you may have a leak in your EVAP charcoal canister near the tank. Also, it will take a few minutes for the light to go out once you replace cap and that was the problem.