Q. I have a 2018 Honda Accord and recently hit 100,000 miles. The dealership recommends replacing the spark plugs, valve cover gasket and a valve adjustment. Do you think those items are necessary, the car runs great. 

A. Typically spark plugs usually get changed around 110,000 miles. If the valve cover gasket is leaking, then certainly change it and if you have the valve cover off it makes sense to check the valve adjustment. Other than if there is a visual issue (oil leak), follow the maintenance minder on the dash and adjust the valves when submenu 4 comes up. Here is what Honda states about early valve adjustment: “Adjust the valves during services A, B, 1, 2, or 3 if they are noisy.” So, if the engine is quiet wait until the car tells you it is time-service 4.

Q. About six months ago I had AAA install a battery in my 2015 Honda CRV in my driveway, a very convenient option. Because of the high temperatures this past summer do I need to check the water level in the battery? During the heat of the day the car is parked about 70% of the time in a garage. 

A. Years back car batteries had removable caps and a good technician would check the electrolyte level when doing an oil change and add distilled water, as necessary. Today most batteries are sealed and require almost no maintenance other than keeping them fully charged, connections clean and battery hold-down tight. That being said continued hot weather can take a toll on a battery. Here in the northeast batteries last five years or more, in Florida, Arizona or other hot weather states battery life is two to three years. 

Q. I have a leaky sunroof with my older Kia Sorento, and I am trying to find out how much it would cost to fix it. 

A. When it comes to vehicles there are no truly watertight seals on every opening. Doors have drains that allow water that gets in between the glass and door to drain. The sunroof also has drains that allow water to drain. If these drains are clogged water can leak into the car. You first need to determine if it is the sunroof gasket and seals or if the sunroof drains are clogged. Carefully inspect the rubber seals on the sunroof opening and clean any accumulated dirt and debris. If the gaskets are in good condition, then using low pressure air check that the drains are clear. At a shop you could expect to pay about an hour’s labor to inspect and clean the sunroof. From that point what the technician finds will determine the cost of the repair. 

Q. I have to schedule my 2009 Cadillac Escalade and my 1998 Honda CRV for air bag replacement. I also have a 2002 Honda Accord and unannounced, a Honda tech showed up at my door offering to replace the airbag in my driveway. Have you heard of Honda doing this? 

A. Some older Honda vehicles were much more likely to have serious issues with faulty airbags injuring drivers than other cars. In fact, Honda hired private detectives to find owners of Honda vehicles to get the airbags replaced. Readers, if you have any recalls on your vehicles get them in for service. If you are not sure download the NHTSA app. It is easy to use, you enter in your vehicles 17-digit serial number and the app will list if there are open recalls that need attention. 

Q. Recently, I purchased a 2018 Mercedes Benz E300, I was under the impression in negotiating with the salesman that I would be able to get a second key as the vehicle came with only one. I was told that they had a key, but it would need to be programmed by a Mercedes dealer, which I can understand. However, I was shocked when told the cost to me would be $600.00! I was caught off guard by that and did not quite know what to say other than “I don’t just have $600.00 lying around”. I have been told that a reputable automotive locksmith could do the work for less, any cost reduction would be great as I am just getting over the initial costs of all this. Do you know of any or could you refer me to an automotive lock smith who could program the key for me? 

A. Some vehicles key programing is relatively easy, but others although possible (with the proper tools and security clearances) seem to be a dealer only service. I called three full-service locksmiths and got the same answer, they could not clone any Mercedes fob after 2014. Sounds like you are headed back to the dealer. Readers, prior to buying a used car, insist it comes with two keys.

John Paul is AAA Northeast’s Car Doctor. He has over forty years’ experience and is an ASE-certified master technician. He will answer readers’ questions each week. Email your questions to [email protected]. Follow John on Twitter @johnfpaul and friend him on Facebook at mrjohnfpaul.