Mechanic’s overblown advice is 50 years too late
Click & Clack Ray Magliozzi
Dear Car Talk:
I love my 2013 Chevy Sonic turbo and it gets great gas mileage. I tend to drive a little on the easy side to maximize the fuel economy and get mpgs in the upper 30s to lower 40s. My buddy, a mechanic, says that I drive too gently and need to periodically “put the pedal to the metal” to “blow out the carbon.” He says this is especially true with a turbo engine, as you need to “make the turbo howl” every once in a while. I know that taking too many short trips can cause problems with the engine not getting hot enough, but most of my trips are in the 15- to 20-mile range. My buddy specializes in hot-rod cars from the 1970s and ’80s, so I think that is affecting his thinking about today’s cars. Or are things different now? — Ed
Your buddy has his headlight firmly implanted in his taillight socket, Ed. Put your fingers in your ears the next time he starts talking to you. There is no carbon in engines anymore. Computer-controlled engines, such as in your Sonic, run so efficiently that they really leave no deposits to “blow out.” The goal of modern engine management is to protect the catalytic converter, minimize emissions and maximize fuel economy. To do that, the engine must burn the fuel as completely as possible, which leaves nothing behind. We almost never see carbon deposits in engines anymore. If we did, they couldn’t be “blown out” by driving hard, anyway. As for the turbo, the more gently you drive, the longer the engine and turbo will last. Period. So yes, I think your buddy is still living in the 1960s and ’70s. Set him straight about modern engines the next time you see him, Ed, and keep doing exactly what you’re doing.
Can you help me identify what is causing a burning oil smell in my car?
We drive a 2011 Subaru Forester X. The engine is leaking oil, and we think it's dripping down on a sensor, which is causing lights to turn on on the dashboard. How can we fix this? -- Mitch
You can fix it by pulling out your credit card, putting a pleading look on your face and handing the card to your mechanic, Mitch.
In our experience, the most common oil leaks on low-to-moderate mileage Foresters come from the valve cover gaskets. The oil leaks down from there onto the front exhaust pipe, which gets very hot. The instant a drop of oil hits that exhaust pipe, it starts to burn, and produces a very strong smell.
That smell wafts into the nearby fresh air vent at the bottom of your windshield, and from there, right into the passenger compartment and up your nostrils, where it causes you to feel lightheaded and seek out brochures for 2019 Subarus. It doesn't take much oil at all to make a lot of smell. A drop or two will do it.
Replacing the valve cover gaskets is not a big deal. It'll cost you a couple of hundred bucks at most. Unfortunately, the higher your mileage, the greater the chance that it's something much worse: the cylinder head gaskets. To replace those gaskets, you have to remove the engine. That's a job that'll cost you over $1,000. Maybe way over.
So, a test is in order. We start by cleaning the whole area because it's always an oil-soaked mess. Then we insert a fluorescent dye into the oil. After running the car for a few hours, we shine a black light on the areas that we suspect are leaking. That usually tells us exactly where the leak is coming from.
If you're lucky, and you've lived a good, clean life, it'll be a valve gasket or two. I've never seen so much oil leak that it shorted out a sensor. So, if you've got dashboard lights coming on, those may be unrelated to the oil leak.
Start by figuring out what's leaking. Then your mechanic can scan the computer and figure out which sensor needs to be replaced.
Once you have the full picture of what it's going to cost to bring this Forester back up to snuff, you can make an informed decision about whether to fix it or grab those 2019 brochures. Good luck, Mitch.
Florida Woman Averts Alligator Attack Using a Small .22 Beretta Pistol
Another good reason to have a concealed weapons permit.
Florida Woman Stops Alligator Attack Using a Small .22 cal Beretta Pistol.
This is a story of self-control and marksmanship by a brave, cool-headed woman with a small pistol against a fierce predator. What's the smallest caliber that you would trust to protect yourself?
Here's her story in her own words:
"While out walking along the edge of a pond just outside my house in the Villages with my soon-to-be ex-husband, discussing property settlement and other divorce issues, we were surprised by a huge 12-ft. alligator which suddenly emerged from the murky water. It began charging us with its large jaws wide open. She must have been protecting her nest because she was extremely aggressive. If I had not had my little Beretta .22 caliber pistol with me, I would not be here today!
Just one shot to my estranged husband's knee cap was all it took. The gator got him easily, and I was able to escape by just walking away at a brisk pace. The amount I saved in lawyer's fees was really incredible. His life insurance was also a big bonus!
DIY mechanic can get started on replacing the starter
Click & Clack Ray Magliozzi
Dear Car Talk:
When I go to start my car (normally the engine is cold), after I turn the key and release it, I hear a grinding sound. This used to happen only when it was cold outside, but now sometimes it happens in the warm weather, too. Could this be the starter? I’ve been using my car to learn how to work on cars and I’ve learned about replacing starters but haven’t done one yet. I don’t want to buy a new starter and try replacing it if that’s not the problem. — Don
I think you’re about to get your big chance to change a starter, Don.
Every starter motor has a shaft with a little gear at one end; it’s called the starter drive. When you turn the key to the “start” position, the starter drive pops out and engages with a much bigger gear called the flywheel, which is attached to the engine.
The job of the starter motor is to use that little gear to turn the flywheel until the engine starts running on its own — it usually takes only a second or two. Then, the starter gear retracts and the engine keeps running. At least, that’s what’s supposed to happen.
If the starter drive doesn’t retract — or retracts too slowly — then you’ll hear that starter gear getting ground up by the flywheel. Grrrrzzzzzzhhhhh!
So, you’re going to fix this by replacing your starter. It’s a job that is within the reach of most do-it-yourselfers, Don, so I have confidence you’ll succeed — certainly after a few tries.
Just remember to disconnect the negative terminal of the battery before taking the starter out so you don’t set your hair on fire.
2007 Mercury Marquis has mixed-up AC air flow
Click & Clack Ray Magliozzi
Dear Car Talk:
The air conditioning on my 2007 Mercury Marquis can never make up its mind as to where to direct the air flow. It comes out the dashboard vents, then changes its mind and sends the air out the defrost vent. Then to the floor. There’s no real pattern. I’ve spent $1,800 at a Ford dealer and the problem never changes.
The first thing I’d check would be the vacuum reservoir. The “blend doors” that direct the airflow under the dash are controlled by vacuum motors. And the vacuum needed to operate them is produced by the downward motion of the pistons inside the cylinders.
Every engine produces plenty of vacuum at idle and at low speed. But when the engine runs faster — as you begin to open the throttle — vacuum drops.
To make sure the blend doors don’t go crazy when the vacuum drops, lots of cars use a vacuum reservoir, which is a simple plastic container, about the size of a Nerf football, that stores vacuum. Its job is to provide vacuum to keep the blend doors from closing and opening haphazardly when the vehicle accelerates.
If that was not replaced, it could be something as simple as a bad connector, hose or check valve. The easiest way to find the vacuum leak (which I suspect is the problem), is to use a smoke machine. In our shop, we will introduce smoke into the system instead of vacuum. If there’s a leak, we’ll see it.
That’s what your Ford dealer, or next repair facility, should do next.
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