Q: In a column last month, you mentioned that a vapor storage charcoal canister can flood if you overfill your gas tank. How would you know if the canister is flooded and not operating correctly?
A: The check engine light will come on. The evaporative emissions control system routinely performs self-tests. If it fails for any reason, including the vapor canister, it will alert you.
Cold means real cold
Q: I have a space heater that keeps my garage between 55 and 60 degrees. I have a compressor, so I fill my tires in my garage, to the "cold" recommendations (44 psi front, 55 psi rear). After being parked outdoors for a few hours during the recent stint of single-digit temperatures, I noticed that my tires were down 2 psi all around. Do I inflate the tires to the outside "cold" level or the garage "cold" level?
A: Cold pressure refers to ambient temperature before the tires are driven on long enough to warm up. You can't go wrong inflating them to the outside temperature.
Shedding light on a law
Q: I live in Pennsylvania and have a 2012 Toyota Tacoma. I installed off-road lights on a bull bar that are operated by an independent switch. When I took the Tacoma to the dealership, I was told that the lights weren't legal. The dealer said that according to state law, because these lights are so bright, they have to be wired in with the high beams. After discussing how much that would cost, I ended up having the dealership remove the lights. Was I misled?
A: Laws vary by state, but a few years ago, I lived in Pittsburgh. So, I'm sorry to tell you, the dealer was correct: Your off-road lights must be tapped into the high-beam circuit. They also must be covered when not being used. (Off-road lights usually come with covers.) According to Pennsylvania law, off-road "lights may be installed if they are not used on a highway or trafficway and are covered with an opaque covering at all times while operating on the highway or trafficway."
A frosty welcome
Q: I have a 2012 Nissan Versa. All the windows, especially the front side ones, fog up quickly when I have the regular heat setting and fan on. I have to switch to defog and high fan to clear them. Sometimes I have to press the A/C button, as well. A garage removed the lower dash panel and said that the knob and cable are OK. They suggested no action unless it becomes a more significant problem. But it's so annoying! What do you think is up?
A: Try setting your controls to outside, rather than recirculated, air. It may sound counterintuitive during cold weather, but you won't notice the difference in cabin temperature. Moisture from your breath, melting snow from shoes and so on raises the interior humidity level, causing fogging.
Bob Weber is a writer, mechanic and ASE-certified Master Automobile Technician. His writing has appeared in automotive trade publications, Consumer Guide and Consumers Digest. Send automotive questions along with name and town to firstname.lastname@example.org.