Q: I bought two front tires for my car that rub under the wheel arch when I make a sharp turn. Turns out the tire shop didn’t put on factory tires. The factory spec for the tires is P215/45R17, but the tire shop installed P215/55ZR17 front tires. The tires rub a bit in tight corners, but not bad. What should I do?
A: The new tires have a nearly 1-inch wider sidewall and are nearly 2 inches longer than the factory-installed tires. This difference can have an effect on braking, handling and overall driving. It was their mistake, and they should install the correct tires at no cost to you.
Q: I am considering an electric car. Should I buy or rent? For the past 20 years, I’ve done both.
A: I’m not a big fan of leasing as a rule (could be a generational issue), but when it comes to rapidly changing technology with electric cars, it might make sense.
The future may be similar to how people think of phones today, where they basically rent the phone from the carrier and upgrade it when the new ones come out. Electric vehicles could be the same.
Q: I’ve always taken my cars to the car dealership because I’ve always felt that genuine (original equipment manufacturer) parts are the best to use. However, I’m never comfortable going to the dealership because I don’t necessarily trust them, because I never know who is working on my car and their skill level, experience, etc. I also feel that many dealerships like to sell services that you don’t need to make money. I also miss that personal relationship with a facility and the person working on your car.
Do independent workshops install OEM parts on request? If not, are the parts they use as good, if not better than the original parts? The only reason I go to the dealership is for genuine parts. Maybe that reason alone doesn’t justify going to the dealership for service.
I simply don’t want to degrade the quality and performance of my vehicles by installing parts that are less superior than those installed when they were manufactured. What do you think about this?
A: Dealerships do excellent repair work, but so do independent repair shops.
When it comes to parts, no independent repair shop wants to install inferior parts and will generally use the parts that have the highest success rate. Keep in mind that many original equipment parts and aftermarket parts are made by the same manufacturer.
Many independent repair shops will use original equipment parts upon request. Very experienced repair shops will know when to use genuine parts. Catalytic converters are a good example.
If you’re unsure about using an independent shop, talk to friends, go to AAA.com/repair, or try a less complicated job like an oil change to rate your experience.
Q: I have a 2012 GMC Acadia with 53,000 miles. Last year when we went to start the car it shook. The stabilitrak/traction control alerts were flashing, as well as the check engine light. It gave off smoke and smelled of gas.
We took the vehicle to the mechanic. They didn’t find a problem. The same thing happened three times in the last month. I asked a friend to check the code and he said failed. As expected, we took it to the mechanic and by then there were no more codes. My mechanic hopes the code is for a specific cylinder and not a “widespread” misfire code this time. Any suggestions if it’s not a specific cylinder misfire code?
A: Over time we have seen deposits in the combustion chamber causing random misfire codes. Carbon builds up in the engine and prevents the valves from fully closing. At this point, if you don’t get a specific code, perhaps ask your store to try a combustion chamber cleaning. The other option is to try a combination of TopTier gasoline and a cleaner such as Techron or Seafoam.
Q: In a recent column, you answered a question about a leaking booster vacuum diaphragm. I have a two-part follow-up question on a hard brake pedal. If neglected, is the condition potentially dangerous? And, in a car with an automatic transmission, could this prevent a car from starting with push-button ignition if the brake pedal can’t be depressed far enough?
A: If the power booster fails completely, the brakes will still work, but it may take two feet on the brake pedal to defeat the power booster.
So if the booster was leaking, you might have to press the pedal quite hard to start the car. Once running, the power brakes would work more or less correctly.
For safety reasons, vehicles equipped with both power brakes and power steering will work when the engine is off, but will require significantly more effort from the driver.
John Paul is the AAA Northeast Automotive Physician. He has over 40 years of experience in the automotive industry and is an ASE Certified Master Technician. Write to John Paul, The Car Doctor, at 110 Royal Little Drive, Providence, RI 02904. Or email jpaul@aaanortheast.com and put “Car Doctor” in the subject field. Follow him on Twitter @johnfpaul or on Facebook.
