Q: I have a 1965 Ford Mustang with a 289 CID engine. (I have owned it since 1975). I drive it only about 400 miles a year. As you are aware, this automobile originally used leaded gasoline, but today only unleaded gasoline is available. With the switchover to unleaded years ago, I started adding lead additive to my gasoline. But in the past couple of years I have not, after speaking with a mechanic who said that I don't have to do that with the low number of miles I drive each year.
Now my problem: When I start the car, it blows heavy black smoke out the exhaust. This occurs every time I start the car, even if it has been parked for only 10 minutes. What is causing this, and should I be worried?
A: I agree with your mechanic about not needing a lead additive. And I don't think the smoke is related to that, either. Chances are it's coming from a buildup of soot in the exhaust system. When you start the engine, that sudden rush of exhaust and water vapor spits some of it out. It is probably nothing to worry about.
Quick change trick
Q: An internet video shows Subaru Outback coolant being drained by loosening the lower water hose. Is there any easier way to drain the fluid?
A: Yes. There is a drain plug at the bottom of the radiator. (You might have to remove a cover to gain access.) But if you are impatient and want to get a bit more coolant out of the engine, the hose technique makes sense. Removing the radiator cap also speeds things up. Be sure to dispose of the used coolant properly by recycling it, not pouring it down the sewer.
Normal behavior
Q: I own a 2021 Honda CR-V. The idle-stop feature stopped working recently, so I had the dealership look at it. They said there was nothing wrong. How can that be?
A: Your car is behaving the way it was designed to. The stop-start system monitors the voltage level of the battery. To prevent killing the battery, the feature is turned off if the voltage drops below a certain level.
Dead is dead
Q: My car has the automatic stop-start system on the engine. If I go out some morning and the battery has run down enough that it won't start the car, can I push the "start" button to start the car's systems, then put on the brake, shift into Drive and take my foot off the brake, letting the stop-start system start the car?
A: I haven't tried this, but I don't think it will work. A dead battery is just that: dead. RIP (Replace It Pronto).
Bob Weber is a writer, mechanic and ASE-certified Master Automobile Technician. His writing has appeared in automotive trade publications, Consumer Guide and Consumers Digest. Send automotive questions along with name and town to motormouth.tribune@gmail.com.
