Yes, you are supposed to have a vented cap. The original one should be vented. They are vented around the edges. Turn it upside down and look around the edges. Should have corrugated type vents around the edges. If it has been fine in the past and all of sudden started this then I don't have an answer. A non-vented cap will cause the fuel pump to pull a vacuum inside the tank though. A non-vented cap should not cause the problem you are describing. ________________________________ From: Sharon Chamberlain <sharonvws@xxxxxxxxx> To: tcb@xxxxxxxxxxxxx Sent: Monday, November 4, 2013 9:26 AM Subject: [tcb] gas gushing out near cap I need some advice on our 67 westy- gas pressure builds up and it runs out from near the gas cap-we were planning on leaving tomorrow morn for Florida shows . Anyone got an idea why and how to fix it. Steve thinks all we need to do is buy a vented cap, we have an original one on there now. Don't want to be a fireball. HELP