Premium fuel - production car - required?

Wow. That's a tough one.

Depends what the car was.

Most modern cars have detonation sensors that will retard the timing if the engine starts to ping, and stop the pinging.

The thing is, running that way, although you won't damage the engine, you also will lose a lot of power. So you're paying for a high compression high performance engine and not getting the performance you paid for.

In the days before electronic ignition controls, that was the case. It was a very quick way to destroy your engine. Today, we have controls to keep you from destroying the engine. But, that doesn't mean using them is a good idea.

And, if the car you're looking at buying is an Mustang with points and plugs, then by all means be careful to prevent pinging.

What does the owner's manual say? If the owner's manual says to use 93, use 93.

--scott

It's probably not a good idea to put much faith in what a salesguy says. Ch ances are they're giving you a standard response to your question. Mostly, you have to experiment with the car in question. If you're not sensitive to engine knock, don't try it cause it's not good to run and engine under suc h conditions.

OTOH, back in the 70s/80s light engine knock was supposed to be acceptable. My experience has been that the ethanol blends will allow you to use one g rade lower grade gas just fine. I used to run my Hyundai Sonata V6 on regul ar grade gas and that had a lot of get up and go. Possibly, it would have h ad even more power with premium but I'm a cheap kind of guy and not all tha t power hungry.

A lot of new cars these days come with an owners manual. You might look in the glove box for one. It will tell you in there whether you MUST burn premium or not.

Unsure how the smarminess is necessary here. Notice I said I was CONSIDERING a new car (i.e. no access to the glove compartment or owner's manual) and that I already KNOW the manufacturer recommends premium fuel. That wasn't the question. Thanks to the people that actually had answers.

Unsure how the smarminess is necessary here. Notice I said I was CONSIDERING a new car (i.e. no access to the glove compartment or owner's manual) and that I already KNOW the manufacturer recommends premium fuel. That wasn't the question. Thanks to the people that actually had answers.

You came to a newsgroup for answers, did you ever try the manufacturers website? My owners manual and maintenance schedules are available online and the site has FAQ and blogs for added information.

The manufacturer's website and the manual will give the standard stock answ er. My experience is that you have some leeway and you just have to test ea ch vehicle to get the real, correct, answer. There's a lot of times where I like to ignore the manufacturer's stock answer.

Pardon me your highness. It took me all of 3 minutes to find this. Based on your comments I assumed you were looking for a high performance civic. Tells you exactly the kind of info you want to know right there in the OWNERS MANUAL. Don't use anything lower then 87. If you want best performance use 91 or higher.

From page 332 of the Honda Civic Manual

2.4L engine models Unleaded premium gasoline, pump octane number 91 or higher Use of a lower octane gasoline can cause occasional metallic knocking noise in the engine and will result in decreased engine performance. Use of a gasoline with a pump octane less than 87 can lead to engine damage.