DEAR CAR TALK: I recently sold my 2009 Lexus ES350. It required premium unleaded gasoline (even noted on fuel cap), and I never had any problems with it.
In March 2019, I bought a 2019 Lexus ES350. I was told by the salesperson that I should use regular unleaded gasoline (also noted on fuel cap).
But the salesperson, and later a service adviser from Lexus, were not able to clearly explain why this new Lexus ES350 should use regular unleaded rather than premium unleaded gasoline.
I am hesitant to use regular unleaded gasoline. Do I continue to use premium unleaded gasoline, or do I save money by using the regular?
I enjoy reading your column every Saturday morning while I drink my cup of coffee. Thank you.
DEAR LUCY: You save the money. And with the money you save, you'll more than pay for every one of those Saturday morning cups of coffee, maybe even a few bran muffins.
In 2009, Lexus wanted more power from the ES350's six-cylinder engine. One way to get more power is to increase what we call the engine's "compression ratio." Basically, the compression ratio measures how much pressure is created in the cylinders when the air and fuel mix is compressed.
So, the 2009 Lexus had what's called a "high-compression engine." The problem with high-compression engines is that they can cause the fuel mixture to detonate too early — before the spark fires — just due to the high pressure. That's called pre-ignition, which causes knocking and pinging that are bad for the engine.
To combat that, the manufacturer requires you to buy a high-octane fuel. The primary characteristic of high-octane fuel (other than a high-octane price) is that it has a higher ignition point. That eliminates the pre-ignition problem.
But it costs you an extra 25 cents or so a gallon. And if you drive 15,000 miles a year, that's an extra $150 in fuel costs. Or $1,500 over 10 years.
You're lucky they figured out how to make an engine in 2019 that's not only more powerful and gets better fuel economy, but also runs on less expensive fuel.
That's called progress.
Your old Lexus made 272 hp and was rated at 23 mpg overall. The new one makes 302 hp and gets 26 mpg overall. Plus, it comes with a free cup of coffee every week to help you choke down my questionable car advice.
DEAR CAR TALK: I recently bought a Tesla Model 3.
My previous car was a 2008 Mini Clubman S. I enjoyed the Clubman immensely, mostly for its legendary "Go-kart handling."
Occasionally, I would enjoy punching the accelerator to experience the full effect of the turbocharger. The turbo would, at times, even be important for avoiding dicey traffic situations.
I know that driving a gasoline engine hard can shorten its lifespan, especially over time.
My question is whether hard acceleration has the same effect on electric cars. It's not that I plan to drive like a drag racer, but punching the Tesla can be so darn fun (within the posted speed limit, of course!).
What's your take?
DEAR JIM: I don't think electric motors really care how hard you "punch" them, Jim. They're designed to go from zero to 100% in an instant, and don't experience the same kind of mechanical stresses that internal combustion engines do.
There are no moving pistons, no rings, no crankshaft, no connecting rods or bearings. That's one of the great advantages of electric motors. Many fewer moving parts.
Of course, the engine (or electric motor in the case of your Tesla) isn't the only thing that can be harmed by hard acceleration. Every part of the car's suspension gets stressed from all that force, along with every nut and bolt that holds the car together.
So, it's not pain-free. And if you drive an electric car hard, you'll eventually develop squeaks, rattles and failed suspension parts like you would on any other car. But it is a heck of a lot of fun!
I think you have it about right, Jim. Once in a while, it's fine to punch the accelerator if that makes you smile.
And if you're concerned about the long-term ramifications, put a dollar in the console between the seats every time you floor it. That'll help pay for the wheel bearings, struts, ball joints and tie rods you'll eventually need.
Ray Magliozzi dispenses advice about cars in Car Talk every Saturday. Email him by visiting:
HomeStyle on 09/07/2019
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