Q: A cat has been scratching the paint on the hood of my Ford Escape when I park it at home. Would I be risking overheating the engine by covering the hood with towels? When I arrive home and the car is hot, I am covering it up and it stays hot for hours.
A: The temperature under the hood will be at its highest when you turn off the engine. It gradually cools down (called hot soak in the industry). All you are doing is stretching out the hot soak period.
A Sirius solution
Q: I have a Porsche Panamera with SiriusXM. Apparently, Sirius sent out an update to the Porsche's PCM [pulse-code modulation], and it caused the system to keep rebooting every few minutes. The solution was a procedure Porsche calls a "handover." They use this when a car is sold or traded in and they want to wipe all the information from the system.
You don't need the dealer to do it. Just google "Porsche handover" and follow the steps. Warning, all your settings will be wiped out, so take a picture of each screen before doing this. When completed, you can request a refresh signal from Sirius. Have you tried this?
A: I've never used it, but I followed your suggestion to check it out online. I found a YouTube video recorded by a Porsche dealer in Tallahassee, Fla. The procedure took only a couple of minutes.
No more 4/40
Q: When I was in junior high, my dad refused to use the A/C, saying it killed the gas mileage. He believed in 4/40 A/C: four open windows at 40 miles per hour. Now I never hesitate to turn on the A/C, and I don't see a lot of gas mileage difference. Do the electronics in today's cars really compensate the gas usage when the A/C is on?
A: Early A/C was, indeed, a power hog. Compressors were large and clunky. System efficiency has come a long way. The electronics in a car are not really a factor.
Don't doubt manual
Q: The manual for my 2016 Mercedes-Benz 450 GLE says to replace spark plugs at 5 years/50,000 miles. But the dealer said we should do it at 4 years/40,000 miles based on the MB 2016 Service Sheet. The dealer says there's a typo in the manual, which I question.
A: You would be surprised how many dealerships print up their own service guides. All they need is some imagination, a computer and printer to make them look professional. Trust the manual.
No change needed
Q: I have a 4WD, 2003 Toyota Tacoma with 162,000 miles, and when I asked the dealership about replacing the fuel filter, I was told it wasn't needed. Nearly every other filter, like air and oil, are changed routinely, so why not fuel?
A: Gasoline is much cleaner nowadays, and gasoline dispensers have filters in them. I've seen cars go hundreds of thousands of miles without a fuel filter replacement.
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 motormouth.tribune@gmail.com.