Car Doctor: Do plug-in hybrids require less frequent oil changes?

Mar 05, 2025

By John Paul

Q. I have a 2023 Toyota RAV4 plug-in hybrid which I drive about 9,000 miles a year. At least half of that is with the electric motor. I would think that oil life would be longer than a fully gasoline engine. I have been having the oil changed every six months. Is this necessary?

A. Toyota recommends a 5,000-mile service, which is nothing more than a series of checkups. Every 10,000 miles, or once per year – whichever comes first, the oil and filter should be changed. Changing the oil and filter as directed in the owner’s manual will maintain the car’s warranty.

Q. In April of 2022, I wrote to you about ghosting on my 2017 Mazda6 navigation system. You were kind enough to send me TSB No. 09-037/21, which addressed the problem. While the factory would not fully cover the touch screen repairs, it helped me to get them to cover part of it. Now we have the same problem with my wife’s 2019 Mazda CX-5. We love these cars, but this issue is maddening. I wonder if you have any updated information that might help resolve this problem with her car. Thanks for all you do. You’ve helped me more than once and I’m sure thousands of others feel the same way.

A. Similar to your Mazda6, the navigation screen is faulty. Mazda published a technical service bulletin 09-003/22 titled “Center Display Peeling or Scrolling,” which is described as ghost-touch. It appears that now there is a screen replacement procedure (similar to a phone screen replacement) which may help with the overall repair cost.

Q. My car has a voice recognition system, and if I call you and end the call and call someone using the voice recognition system, the car phone does not clear you out. I went to my dealer, and they reset my car system, which did not help. The dealer told me to call my provider, Verizon. Verizon said it was not my phone, and I had to go back to the dealer. Now what?

A. I drive dozens of cars over the year and phone compatibility can be an issue. I have an iPhone, and my wife has an Android. Some cars’ phone features work better than others. The first thing to do is make sure your phone is running the latest operating system. Then, if the features you want are not working, check with the dealer and see if there are any software updates that may help. Unfortunately, there are times when these sophisticated electronic systems are just not compatible with each other. Sometimes it is more important to “road-test” the technology as much as the car.

Q. Recently, someone wrote to you about the growing problem of deer on our roads. A couple of years ago, I purchased small deer whistles that easily attach to any vehicle and are very inexpensive. As you drive, the air rushes through the whistle which emits the deterring sound. Humans cannot hear the whistle, but the deer can and do. I’m very pleased to report that I’ve not had any deer cross in front of my car since attaching the whistles, although, from some distance, I’ve seen deer darting away. I made my purchase from Amazon; just search “deer whistles for vehicles.”

A. I am glad these whistles work for you. I have also talked with drivers who hit deer and then put whistles on their car and never hit another deer. However, science is not conclusive as to whether these whistles work. A study was published years back by the “Journal of Wildlife Management” that concluded that whistle-like noises do not change deer behavior in any way. Readers, have you had success with deer whistles? Email me.

Q. I was watching an automotive program and watched the mechanic repair a wiring harness using a crimp connector. This seems like extremely poor advice. To me, any wire should be soldered, not some crimp connector.

A. Times have changed. These special crimp connectors are the factory-approved method to repair wiring harnesses. In fact, years back I was at the local General Motors Training Center and the crimp repair was what was recommended for broken ABS sensor wiring. Today, Toyota, BMW, and General Motors, specifically in their repair manuals, do not recommend soldering but rather crimping.

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 Doctor question to [email protected]. Listen to the Car Doctor podcast at johnfpaul.podbean.com.

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