Q. For the past few months, I’ve occasionally had trouble starting my 2015 Nissan Sentra. The dealer first said it was a weak battery, but after replacing it, the problem persisted. Then they said it was the brake switch. When I put my foot on the brake pedal, it doesn’t go down. I wait four to six minutes and it usually starts. I’m a senior and afraid that one day it will not start at all, so that prevents me from driving outside my very local area. Do you have any suggestions??
A. The hard brake pedal may be a clue. The Sentra has a smart key — its push button start requires that you push on the brake pedal to start the car. I think the dealer was on the right track in replacing the brake switch. I suspect the brake power booster is losing vacuum. The problem could be a leaking brake power booster or even condensation in the booster vacuum line.?
Q. What do you think of the Hyundai Sonata hybrid? With all of the problems Hyundai had with their engines in the past few years, would you trust the engine in the hybrid to last??
A. Hyundai certainly had its share of problems with two certain engines that would basically self-destruct and catch fire. It appears that the problem was remedied in the 2018 and newer models (time will tell). The engine in the new Sonata hybrid is not subject to any recalls. Regarding the car itself, it is an extremely good car. The ride is comfortable, five adults can fit in the car with reasonable comfort, and the fuel economy is outstanding at 52 miles per gallon, according to the trip computer during my test drive.?
Q. Is there anything we can do about alloy wheels that cause tires to lose air during cold spells? It’s ridiculous to be constantly going to the air pump or the mechanic for air. I have even had the repair shop use an anti-oxidizing lubricant on the wheels to prevent corrosion, but still need to add air.?
A. About all you can do short of replacing the wheels is to try again to clean and seal the wheels. Dismounting the tires, cleaning up the corrosion, and then applying a quality bead sealer can sometimes work. General Motors years back would recommend dismounting the tire, cleaning up the rim with medium-coarse sandpaper and carburetor spray, and sealing the leaking area with silicone gasket cement. A couple of years back a reader who had a leaking wheel cleaned the wheel with alcohol, coated the wheel with FlexSeal, let it dry overnight, and had the tire reinstalled. Personally, I have had pretty good luck buffing/sanding the wheel where the tire bead locks and then using plenty of bead sealer.?
Q. I had to drive home in the snow one day and my windshield wipers kept getting clogged with ice and rising off the windshield. I would have to pull over and knock the ice off only to have it happen again in another 15 miles. What can I do??
A. The first place to start is to make sure your car’s defroster is working properly and directing plenty of air to the windshield. Also be sure the engine is getting fully up to temperature. If everything is operational, switch your wiper blades to an all-weather or winter blade. These blades are a beam design or use a cover (metal, plastic, or rubber) to block ice from building up in the fingers of the wiper blade. The all-weather blades are a bit more expensive, but in my opinion are worth the money.
John Paul is AAA Northeast’s Car Doctor. He has over 40 years of experience in the automotive business and is an ASE-certified master technician. E-mail your car question to [email protected]. Listen to Car Doctor on the radio at 10 a.m. every Saturday on 104.9 FM or online at northshore1049.com.
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