ASK THE AUTO DOCTOR
Q: I have 2014 Cadillac ATS with 15,000 miles and the 3.6-liter engine. The dealer insists on a throttle body cleaning. Is this necessary with such low mileage? — Alan.
A: I would get a second opinion and ask a technician to take a look at the actual throttle body for his opinion. The use of a good fuel additive, such as Seafoam or Techron, every other month is money well spent especially with such low mileage.
Q: The interior lights on my 2003 Ford Explorer remain on after I get exit the vehicle. And, the driver’s door lock switch fails to work. Are there any easy fixes? — Jack.
A: Check the body control module for trouble fault codes. I have seen many sticking and frozen door light pin switches. These switches are located in the door latch, requiring that the interior door panel be removed to access the latch. In some cases you can buy just the switch and in other cases you need to buy the latch assembly.
Q: I own a 2007 Honda Accord with 140,000 miles and needed roadside assistance to jumpstart the car. I was told I needed a battery, a starter, and an alternator. I had my mechanic replace the battery and starter, but he stated the alternator was working properly. Since the service work was done whenever I don't start the car every day, the battery dies. My mechanic can't help. What type of troubleshooting tactic is used to determine where the drainage is coming from?— Herbert.
A: The first step is for the technician to perform a load test on the battery, even though it is new. You also have to make sure the battery has the correct CCA rating. The higher the cold cranking amp, the better. You can start by checking the vehicle's lights including dome, glove box, and trunk (if equipped). If the battery checks out good, then the next step is a check of current load. This is performed with an amp meter connected to the battery cable in series or with a clamp-on style inductive meter. The technician will check the milliamp current draw. Anything between 50 to 75 milliamps is considered exceptional. Next, the technician will start pulling one fuse at a time and observe the current draw. I have seen this caused by radios, clocks, power seats, door locks, and even alternators. Anything that uses 12 volts while the key is in the "off" position is suspect.
Q: I will be buying a 2019 GMC Canyon SLT 2WD this fall. It has been reported that a twin-turbo four-cylinder gasoline engine might be offered. What are the advantages and disadvantages of a turbo over the V-6? — Ken.
A: The 3.6L V-6 has 308 horsepower and max torque of 275 lb.-ft. at 4,000 rpm. Specifications are not available at this time on the twin-turbo engine. Right now I like the V-6. I would recommend before buying the GMC to look closely at the new Ford Ranger and Honda Ridgeline pickups.