The gas cap on my 2003 Pontiac Vibe used to make a slight sound of "pssstt..", the sound of some air either entering or exiting from the tank as I was opening the cap.
Two months ago, the gas cap stopped making that sound when I unscrew it to fuel, even though I still tighten it quite firmly after fueling.
At just about the same time, the "check engine" light has gone up. The OBD reader says that the "catalytic converter bank one sensor" is faulty. But before I replace it, I want to clean the gas cap thoroughly to rule out that the coincidence of the lack of air release sound and the check engine light is not just a coincidence but rather a cause and effect.
I see here instructions for cleaning the gas cap. In summary:
- Clean the metal part (the top of the gas tank intake) with a "petroleum-based lube".
- Cover the rubber seal on the gas cap with a "silicon-based spray" to prevent the petroleum-based lube from deteriorating the rubber.
Are these instructions accurate?
I'll throw in a silly question: Would Vaseline-brand 100% pure petroleum jelly (the one used for baby diaper rash) be a suitable "petroleum-based lube" or is a car-specific product needed?
And if I use a 100% cotton fabric to clean the top of the gas tank, does this suffice to minimize the chance that I'll generate a spark that blows the tank on me?