Can You Use Regular Gasoline in a Premium Car?

I used to own a car that requires premium gasoline. Then I started putting in regular gasoline in. For six years. My engine didn't explode and everything was fine. Of course, that's anecdotal but the science behind it also supports the idea that your engine really wont explode if you do so.

EDIT: After reviewing all the comments, I have to add that if you do try to use a lower octane fuel, you may need to double check there is no 'knocking' in the engine not just audibly but with an ODBII reader. The reader will record every single instance of a knock or 'backfire'. While using lower octane once to test it out is unlikely to cause engine damage, using it continuously with the engine knocking could damage the engine. Hence, if you do this, you really need to know what you are doing.

Also, it probably doesn't work so well with engines with turbos. Turbo engines work with increase pressure and so a lower octane will cause it to knock. Depending on the engine, it may or may not be able to compensate.

Other BeatTheBush Channels:

[BeatTheBush]

After reviewing all the comments, I have to add that if you do try to use a lower octane fuel, you may need to double check there is no 'knocking' in the engine not just audibly but with an ODBII reader. The reader will record every single instance of a knock or 'backfire'. While using lower octane once to test it out is unlikely to cause engine damage, using it continuously with the engine knocking could damage the engine. Hence, if you do this, you really need to know what you are doing.

Also, it probably doesn't work so well with engines with turbos. Turbo engines work with increase pressure and so a lower octane will cause it to knock. Depending on the engine, it may or may not be able to compensate.

[CurieBohr]

My uncle runs the entire repair shop at Mercedes. He says they see so many come through with damaged motors because owners do not use 91. First sign of damage will be a very low knocking sound. Takes years. But will destroy your car. 91 is the minimum. Where 93 is available, it’s suggested.

[lihtan]

Back in the day, I had a car that was intended for lower octane fuel, but I fully advanced the ignition so that it would run on premium. Although the fuel cost was higher, it was offset by the improved efficiency of the motor. This was a fuel injected vehicle, but it used an OBD-1 system that wasn't equipped with a knock sensor.

[Barmargroup]

Back in the 80's it was common to hear knocking at 87, so I used 93 octane but it was only $.20 a gallon more back then. Today the quality at 87 is better because the government made them clean up the gas with detergent I was told in about 2011. I bought a used 99 Lexus that required premium in 2018. I tried 93 and 87 because of the roughly $.60 difference in Illinois today and I notice no knocking and the gas mileage was identical. I have put 60, 000 miles on it in 4 years and its still running well at 271, 000 miles on 87. Sometimes I put a booster in the tank but I also don't try to dog it while driving as well. Just my experience.

[ascendantP]

This video needs a disclaimer to, "Don't sue me bro". You should follow the recommendation of your owners manual, some manufactures say its fine not to use the recommended premium fuel octane, some do not and even warns that this can void any warranty claims if this is discovered to be the case if you are having engine troubles. Porsche engines are built like a tank and it rarely has timing/knock issues from using a lesser octane fuel. However, Mercedes, BMW, and Audi engines are more sensitive and can cause issues if you are using less octane fuel for years

[mindibear]

My car gets 29mpg when I use Premium and 26mpg when I use Regular. Regular gas is cheaper but I needed to fill up more often so it was a wash. I also had increased performance with Premium so I decided to stick with Premium because in the end it costs the same and I don't have to fill up as often.

[deborahdownie]

Very helpful, information. We are looking at a new Cadillac and they recommend using premium gas. You did a very good job at explaining why it’s not really necessary.

[PresidentEvil]

you really shouldn't be using regular in a premium gas car, the engines are just not designed for it and you are risking knock and potentially destroying your engine, all to save a few bucks
premium also has additives that help engines run cleaner.

[rockyzman]

Thank you for the video. I actually watch this video on my tablet when it first came out but as in all your videos I will usually watch them several times. I learn and am inspired by your videos. Once again Thank you.

[ronlam]

My recommends 91 octane. I tried 87 octane once, and the check engine light came on while i was cruising on the highway. I wasnt even putting the engine on load as i was driving with low rpm.

[Weathernerd]

Most cars are meant to run on 87 if you're car requires 91 there will be a sticker on the gas cap. Putting 87 in a 91 car wont cause immediate damage although over time there could be problems and the cars performance will be slightly worse. Often times 91 gas is actually a mixture of 87 and 91 because the gas station orders too much 87 and the manager says throw the extra in the premium tank. If you want to take good care of you're engine using top tier gas is better than using premium.

[caezar]

Would only do this if you have a naturally aspirated vehicle with no turbo.

The higher the octane, the more resistant the gas mixture is to pre-ignition, especially when the turbo is forcing air (and hot air at that) into the combustion chambers. Modern engine management computers can retard timing to limit (but not necessarily stop all) pre-ignition, which is harmful to your engine especially at full boost and high RPMs, but doing so will cause a rise in exhaust gas temperatures which will cause the turbo to heat up more, and since the turbo is oil cooled, the oil temperatures will go up locally, and if the engine is shut off suddenly, the turbo can "cook" the oil leading to a build up of junk in the lines, causing a oil starvation and turbo death.

The remedy is to use the recommended octane rating for your car, at least if you have a Turbo and it recommends premium. Not to mention the reduction in mileage with the turbo will be especially noticeable with regular gas.

[dumbcat]

Chris Fix did a video about this. He said it depends on if your car has a high compression engine. He said if your car has a high compression engine then you should NOT use regular gas, as you can destroy the engine.

[Aznmf]

Don't buy a truck or a SUV if you're not willing to fork over $$$ for the gas. It's 2008 all over again. You have the freedom to drive more or less, gas efficient or gas guzzler.

[johnstepp]

At the moment I am driving a car and using a premium grade.
Because it uses slightly less gasoline and thus it pollutes slightly less. That and because I really don't think my car even has a ping detector.
At one time we had a Davies brothers station in my area and they charged 15 cents more than the price of regular, kind of missing dealing with honest oil companies.

[vnoljnl]

This guy is Wrong, don't you DARE put that bs gas in your premium car. It will cause a difference and you will notice it. Engine issues are verry expensive. he won't be there when the issues start.

[JohnSmith-ijxe]

FYI it’s not just turbocharged engines but supercharged engines also. Rule of thumb is to do whatever the manufacturer says is ok as in recent years some engines are under higher compression so they require 93 and manufacturers state 91 is ok BUT nothing lower. Your statement is current 20 years ago when they pushed manufacturers to require all new cars sold run on 87 but they quickly backed down due to all the push back so if the manufacturer says 91/93 is required then you must run it or you could void your warranty and or damage the engine. Do what manufacturers require only. Never do what someone may say is ok.

[Barmargroup]

I was also told high octane will get you 30% more mileage on your tank years ago. That has never been a reality for me.

[Chief]

Your missing a membrane bro, you just broke 100 Mercedes Thnks to your video coming from a Mercedes mechanic your the reason y I’m busy

[DarkLinkAD]

Its not as cut and dry as this. My 3.8 Impala would knock on reccomended 87 octane (not audibly, confirmed with an obd ii scanner), 4.6 Cobra would knock audibly, light throttle, uphill only with anything less than 91. (91 reccomended)

Some vehicles see false knock and retard the ignition timing, makes your car lazy, like a hot and tired dog off the line.

Basically, unless you have a way to see knock, while driving, you wont kbow how good of a job your vehicle is doing, even with an oem tune. Just one more reason to have your vehicle custom tuned(by a reputable source) on day 1.