John Paul is AAA Northeast’s Car Doctor. He has over 40 years’ experience in the automotive business and is an ASE certified master technician. He will answer reader’s questions each week You can find the Car Doctor podcast at www.johnfpaul.podbean.com or other popular podcast sites. Email your car questions to [email protected] Follow John on Twitter @

Q. I own a 2015 Ford F-150 with the Eco-boost engine and only 9,300 miles on it.  When stopped at a red light the engine would shut off as it is supposed to and then would restart when gas pedal was applied.  Now, it no longer does that.  It was checked by a Ford dealership mechanic, but he could find no reason for this.  I’m hoping you know more than they do. 

 A. No one should know more about your Ford truck than a Ford technician. For the auto stop system to work certain criteria need to be met. These include engine temperature, engine load (air conditioner on/off), trailer towing, brake light switch and charging system operation. It is possible that with such low mileage on a seven-year-old truck the battery state of charge is low enough that the computer won’t signal to shut off the engine. The first step in diagnosing this problem would be to check to make sure the battery is at full charge of at least 12.6 volts.

Q. I have a 2000 Toyota Landcruiser and the air conditioner button is always on when the heat is turned on.  It was supposed to turn off and on if you press the button, but it is always on. It always used to work this way.  It appears to just be stuck on. How do I make it properly functional again?

 A. The climate control system in your Landcruiser has a diagnostic mode and the diagnostic test should be performed first. The problem could be as simple as a shorted switch or relay, but a diagnostic inspection is the first place to start.

Q. Are the MPGs listed by the manufacturer for their hybrid models realistic, or would they fall short by every day driving? In other words, what kind of driving behavior would a driver need to follow in order to meet or get close to the MPG estimates touted by the car manufacturers in the vehicle descriptions?

A. I have driven many hybrids and found the mileage very realistic. Like any vehicle, mileage is mostly controlled by the driver, quick starts and high speeds will affect mileage. Drive reasonably at the posted speed limit and mileage is easily attainable and sometimes exceeded. Drive a Prius at 80 MPH and you will never get 50 MPG.

Q. My car is a 2018 Volkswagen Jetta with only 12,000 miles on it. I’ve owned it since 2016 and put maybe 7000 of those miles on.  Recently I’ve noticed that when I start up, the dashboard display (odometer and tachometer) do not light up.  Eventually, they will light up, but may (or may not) go back off for a while. I can get them to light by switching on headlights and, yes, it does not appear to affect the daylight running lights.  Most recently, I found that if I lower the driver’s side window the lights will come on, but they go off as the window is closed.  The problem seems to be related to moisture, but I haven’t been able to pin it down to the point where I can tell a service tech what’s happening.  Any idea?

 A. I would suspect some sort of poor electrical ground. At this point a series of voltage drop tests need to be performed as well as a basic test of the battery. When putting the window up and down you are putting more of a load on the electrical system causing voltage to vary.

Q. I just bought a 2021 Jeep and would like to know if there is a way to get better fuel millage. It has the V6 engine and I am getting around 12/14 miles per gallon in the city and at best 20 miles per gallon on the highway.

 A. I would expect to see about 15 to 16 miles per gallon around town and 22-24 miles per gallon at a steady 60 miles per hour on the highway. The winter gasoline sold this time of year has less energy and you can lose up to 10 percent of your fuel economy. If your Jeep has a remote starter and you use that regularly, fuel economy can be reduced dramatically. At this point, check and inflate the tires to the correct specification and look at your own driving habits. Fuel economy can be improved by driving reasonably, easy on the gas and brake and staying at the speed limit.  Depending on the mileage on your Jeep it can take up to 10,000 miles for the engine to fully break in.