Hello, I have an 01 X5 with 109K miles. I had this light come on a year ago or so, all I needed was to get a new cap. Now the light is on again and I'm wondering if it needs another cap or something more? Does anyone have any input on what this could be??? I've done a search but nothing besides the gas cap or just plan bad gasoline come up. I put shell premium all the time. Engine runs smooth and quite, has plenty of pick up. Thanks