Car Guides

Why can’t car technology predict future problems?

John Paul, AAA Northeast's Car Doctor, answers a question from a reader wondering why car tech doesn't anticipate upcoming maintenance issues.

The steering wheel and dashboard of a General Motors Co. Buick Velite 6 electric vehicle (EV) is seen at the company's dealership in Shanghai, China, on Thursday, July 18, 2019. Gilles Sabrie/Bloomberg

Q. I have an eight-year-old Chrysler. It’s a good car but it’s starting to develop some problems. First, the battery died. Next, a computer sensor failed, and now the starter is acting oddly. With all the computers in cars, as well as all the add-on accessories, why isn’t there something that can tell me when something is going to go wrong, before it does? 

A. Wouldn’t that be nice with everything — cars, houses, and people? General Motors uses On-Star to alert the driver if there is a pending problem, and other manufacturers, where vehicles have their own internet address, can perform similar functions. Even with this technology I still recommended having your trusted repair shop give your car a once-over at least yearly to access its overall health. I recently read about a plug-in device that is capable of predictive diagnostics. The device is designed to alert the owner or repair shop if an electrical component or system is getting ready to fail. The company is Carmen out of Singapore, and I will be testing it in the near future. 


Q. In December of 2019 I had to have the battery replaced in my 2016 Toyota Camry LE. I went to the dealer maintenance shop with approximately 243 miles until the gas tank was empty, according to the fuel indicator. When I picked up my vehicle, the miles to empty was 303 miles. I brought this to the mechanic’s attention immediately, telling them 303 miles to empty is what I get on a full tank, and the tank was only half full. They said they don’t touch those monitors and that it would readjust as I drove the car. I fractured my foot two days later and was not able to drive until March 2020. To make a long story short, the miles to empty did not adjust. When I took the car in for an inspection, I spoke to a manager again and was told that when the battery is changed, I should also have the throttle body and fuel injection service done for $300. Is this true? Are these services necessary and do they affect the battery or how the car runs? I waited until the gas meter was down to a quarter tank and filled it today. Miles to empty came up as 388 miles.


A. When the battery was replaced, the car’s computer memory was erased. The on-board computer that measures miles per gallon was reset. The new calculation is based on the day the battery was replaced, and over time, the average will adjust to a number you are more familiar with. Regarding the fuel injection and throttle-body cleaning, it can’t hurt but it won’t change the miles-to-empty number. If the car is running well, it’s not something that I would spend my money on. 

Q. My car has a dent in the middle of the door. It looks like someone kicked a soccer ball at the door. It is an older Ford Windstar that is not really worth putting any money into, but the dent looks ugly. I have seen various tools online to remove dents, do these work? 


A. Most of the tools are some type of suction device. If the dent doesn’t have a crease in it you may be able to pull it out. Without spending any money try this. Pour hot water on the dent then attach a plumber’s plunger and give it a pull. You may find after multiple attempts you get the door looking acceptable. 

Q. My 2005 Hyundai Sonata has developed a new noise. As I back up, the car makes a whirring noise which gets louder as I continue backing up. My mechanic told me this is normal for a Hyundai or any car with lots of miles. What do you think? By the way, this Hyundai is the best car I have ever owned. 


A. I would certainly get a second opinion. The noise could be internal to the transmission and an expensive repair that may not be worth investing in at this point. Then again, the noise may be a wheel bearing or brake issue that could impact your safety. If this were my car, I would get a second opinion just to be safe. Even the best car ever can eventually wear out.

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]

Jump To Comments


This discussion has ended. Please join elsewhere on