A cold engine needs extra fuel because gasoline does not vaporize easily. (Dreamtime/TNS)
Q: I seem to recall being told many times that the engine should not be revved for the first time because the oil has not yet reached all the components (or something like that). If this is true, why do the engines idle so high when you first start the car? Touching the gas pedal does not seem to lower the idle speed. Bow down to your wisdom.
AA, Bethlehem, Pennsylvania
To: During the cold soak (the industry term for sitting for a while), some oil escapes the components, but not enough to cause damage to begin with. A cold engine needs extra fuel because gasoline does not vaporize easily. In the old days, the choke restricted air, resulting in a richer fuel mixture, and you could tap the gas pedal to release the choke and high idle. Fuel injection maintains the proper amount of gas and engine speed. Now you can kiss the ring.
Q: I have a 2021 Subaru Outback and the headlights are pointed too high. Dealer says they are not adjustable. Isn’t this a safety hazard for the oncoming driver as well as for me from road rage?
JB, Tully, New York
To: This is a somewhat common complaint. I think the headlights can be adjusted. All you or your auto tech needs is a very long Phillips screwdriver.
Q: I have a 2010 Ford Fusion Sport. I love it. The tire pressure sensor error message appears on the dashboard. This he has done before he magically disappeared. They recently put on a new set of tires and although not immediately, the error message is back. My mechanic says they can plug in a device that can find a fault, but somehow if a fault is found in one, it can give an incorrect reading of another fault. So would it be better to buy a new set of sensors and replace them all rather than possibly find just one faulty sensor?
DW, Virginia Beach, Virginia
To: TPMS (tire pressure monitoring system) sensors for your car come in a 4-pack, costing about $50. Get them all and enjoy peace of mind.
Q: I recently had the oil changed on my 2019 Hyundai Elantra GT and when I left the dealer’s service area I noticed a louder than normal engine “grunt” while accelerating from a standstill to 25-30 mph . The sound seemed to stop at that moment. I love the Elantra, but it’s not the quietest ride I’ve ever had, so I didn’t think much of it. This continued for a couple of weeks before I decided to go back to the dealer to have it checked. After about 15 minutes the service guy came out and told me the “air box” had been left open, I guess during the oil change. He said they closed it and it wouldn’t have caused any problems. Sure enough, as I walked away, the grunting noise was gone. I had never heard of an air box. Is it a real thing? Is it ok to drive when it’s open?
RK, Michigan City, Indiana
To: The air box houses the air filter. It’s fine to drive with it open some of the time, but not all of the time. Your engine doesn’t like to suck up dirt. Since the air filter is under the cover, it has been doing its job without the cover.
Bob Weber is a writer and mechanic who became an ASE-certified Master Automotive Technician in 1976. Weber’s work has appeared in trade magazines and various consumer publications, including Consumer Guide and Consumers Digest. Send questions along with name and city to motormouth.tribune@gmail.com. This column was distributed by Tribune Content Agency.
