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Search result for: 88 octane
| # | Post Title | Result Info | Date | User | Forum |
| When I use 87 octane my engine knocks. When I use 91 or 93 it doesn't. | 29Relevance | 4 years ago | SchwarzeneggerPlease | Submit Your Question HERE | |
| Scotty, I have a 2015 Kia Optima. 104k miles. 2.4 liter. GDI. Automatic. When I use 87 octane my engine knocks. If I use 89 octane it doesn't knock as much. If I use 91 or 93 octane the engine doesn't knock at all. Could it be a dirty fuel filter, or do I need to get the injectors pressure cleaned? Could it be something else? I also get a high pitched whine when accelerating hard above 4000 RPM. Thanks. | |||||
| Answer to: Do all turbos require premium fuel | 40Relevance | 5 years ago | Dad2LM2 | Submit Your Question HERE | |
| Normally, the air-fuel mixture in the cylinder is compressed (during the compression stroke), and the spark plug fires at the top of the stroke to ignite the fuel. But compressing a gas itself raises the temperature of the gas, and if you compress it enough you can spontaneously ignite the fuel (this is how a diesel engine works without spark plugs). Turbos and superchargers pre-compress the air before it enters the cylinder in order to increase the oxygen available for combustion. The problem with using low-octane fuel in older turbo cars is that at the higher pressure, you can get spontaneous ignition before the cylinder reaches the high point of the compression stroke (ie, pre-ignition), which causes knocking and can eventually damage the engine. You can overcome this by using higher octane fuel, which is less prone to pre-ignition. That is why most high-compression engines, including most turbos (like my 2018 WRX) and even some naturally-aspirated engines (like the hemi V8 in my wife's Grand Cherokee), specify premium gas (91 or 93 octane). However, most modern, computer-controlled, cars are able to automatically adjust the air-fuel mixture to avoid pre-ignition when using lower octane (87) gas; it comes with a loss of a little horsepower and MPG, but it won't damage the engine. Seems like most turbo cars I have seen recently recommend premium fuel in the owners manual, though they state that you can use lower octane fuel if you have to. I have never seen one actually recommend 87 octane for a turbo engine, but I don't see why not. My guess is that if you ran 91 or 93 you would get more power and MPG, but that the difference isn't enough for the engineers to recommend it. If the difference is minor, it would just be a waste of money, but it wouldn't hurt anything if you wanted to test it out for yourself. | |||||
| Answer to: Ethanol free gas? | 40Relevance | 5 years ago | Razmig Bartassian | Submit Your Question HERE | |
| Keep in mind that gas without ethanol has less octane compared to ethanol-blended gas. The whole point of blending ethanol in gas is to raise the octane and to have cleaner burning gas. Pure ethanol has an octane rating of 113, whereas pure gasoline is 85. You'll notice that pure higher-octane gas is more expensive because they use non-ethanol additives to increase the octane (anything race fuel oriented is expensive). Honestly, if anyone feels any difference between ethanol and non-ethanol gas, then it's all in your head. There's no way you'll be able to feel a noticeable difference with only 10% blended ethanol, let's just be real here. I have tried pure E0 91 octane in my BMW before (as I've mentioned numerous times before, I like to experiment around with this stuff)...no difference at all. | |||||
| Answer to: Octane 88 not good for octane 87 engines? | 38Relevance | 2 years ago | Chuck Tobias | Submit Your Question HERE | |
| Yes, the warning has nothing to do with the octane rating. Modern engines (aside from "Flex-Fuel") are designed for a maximum of 10% ethanol contamination in gasoline. Higher levels may damage the fuel system. Most older vehicles can also tolerate 10% ethanol, particularly if rubber fuel system parts have been replaced which should be done on a decades-old vehicle in any event. I certainly wouldn't want to try a 15% concentration though. | |||||
| Answer to: Is 91 octane needed ? | 36Relevance | 2 years ago | avalon04 | Submit Your Question HERE | |
| The publication ‘Car and Driver’ indicates in it’s listing of specs for the 2014 Scion that premium fuel is required. The website: http://www.fueleconomy.gov also indicates that premium fuel is required for this vehicle. (those are the only two sources that I checked.) Mixing 7.5 gallons of 93 octane gasoline with 5.5 gallons of 87 octane in your 13.2 gallon capacity fuel tank actually yields 90.46 octane, LOL. (accounting for the 0.2 gallons which would be remaining in the fuel tank if you are able to drive it to the gas pump) But I am not sure if that is how mixing octanes can be calculated or measured. I do not know the long term deleterious effects of using a lower octane in your vehicle. But if 93 is available and premium fuel is required, then the higher cost you pay now may be much lower than the cost of engine, etc. repair later. | |||||
| '08 Honda Fit w/ 206k synth oil change intervals? 93 octane. Man trans drain/fill. | 36Relevance | 5 years ago | goatbelly | Submit Your Question HERE | |
| Hi and thanks for your time and honesty. I recently purchased a one owner, very clean inside out, no stains, factory grey paint, no mods, clean title, manual trans '08 Fit base model w/ 204k miles in very well cared for condition without hesitation after proper pre purchase inspection. It had a fresh oil change upon purchase. I did my first oil change after 2,500 miles using Kirkland 5W-20 full synthetic and a NAPA (Wix) Platinum oil filter and am curious on how many miles to wait for the next one? Normal city/highway driving rarely shifting over 3k rpm and 75-80mph on highway very smoothly. Also, The idle was good but could be improved so the first 2k miles I used 87 octane except when using a 12 oz. Chevron Techron FI cleaner every 500 miles (4x) with a 93 octane full fill from empty. When using the 93 octane it was great and even better with synthetic oil making it feel like a 30k mile car. Will using 93 octane hurt anything if using it long term. One more thing, the 5spd shifts great, but I'm contemplating on possibly changing the trans fluid due to the high miles, NO flush, just fill with same amount taken out or let it alone? Being a very well cared for Honda, I plan on doing the same care and doubling the milage it has and then some. Thank you again for everything honest, Rob G | |||||
| RE: Octane Booster Question | 29Relevance | 4 years ago | DontKnowler | Submit Your Question HERE | |
| "Do you have any literature" Not really. Read it many times in many sources, but all those sources were in Russian, sorry. However the English Wiki also says: "Because of the 8 to 12 octane number difference between RON and MON noted above, the AKI (Anti-Knock Index) shown in Canada and the United States is 4 to 6 octane numbers lower than elsewhere in the world for the same fuel." (RON and MON being different octane index measuring methods used in different countries) | |||||
| Answer to: Octane Booster Question | 29Relevance | 4 years ago | DontKnowler | Submit Your Question HERE | |
| "my car requires 91octane or better"You did not indicate what country you re in. As far as I know, 525i requires the _European_ 92 octane. Off the top of my head, the European 92 octane approximately equals the US 87 octane = the US regular gas. | |||||
| Recommended Octane for Holden 202 engine (1978 Holden HZ Kingswood) | 36Relevance | 5 years ago | erebusreactor | Submit Your Question HERE | |
| Here in Australia, we have 3 common octane ratings available. 91, 95 and 98. I own a Holden Kingswood from 1978 with the 202 inline 6 cylinder engine which was obviously designed to run on leaded fuel. Please keep in mind things might be different here in Australia with fuel etc. than America. My question is (I am also using a lead replacement additive) which fuel octane would be most suitable? I am not sure how high octane the fuel would be back when the car was made in 1978. For any Americans reading this, Holden was a brand under General Motors so the engine likely shares many similarities with Chevy inline 6 engines of the time period. I know 91 is probably too low octane, I currently use 98 but just wondering if I should perhaps be using 95 instead alongside the lead replacement additive I am already using. | |||||
| High octane gas probably did some damage to my car | 36Relevance | 5 years ago | Cloud Shade | Submit Your Question HERE | |
| Hello! I know, it's a little strange to write here because I'm from Russia, and no one probably heard about my car model, but anyway... It's a 2008 Lada (VAZ) Samara 2114, four cylinder, eight valves. So, I was running 95-octane gas and was pretty happy with it. The car was rated to run on such gas, so everything went fine. Beforehand I had an intercooler replaced, because it started leaking. With a new intercooler, my car was still getting pretty hot, especially with 95 gas. It was very apparent when idling at stop lights - the fans were engaging and it was very noisy. My point is, on 92 gas it was better. Well, at least in terms of temperature... But when I went back to 92 to remove the overheating problem, my car lost torque. It was especially apparent when trying to start from a stand-still. Pressing the throttle all the way and not getting the power made me nervous, and yeah... I went to a gas station and bought some high octane gas. Not 95, not 98, but 100 gas. The highest you can get in Russia. And then true problems began... After starting the engine next day I noticed huge misfiring problems. The engine was vibrating like crazy, stalling while idling. But I still had to drive, so that's what I did. I was driving 80-90 km/h on a highway for 10 minutes, and after stopping at a stop light, i noticed steam coming from my engine. The coolant was fine, 92 degress Celcius. But the engine sure did overheat. I went to a parking lot to investigate, and sure thing, there was a lot of steam, and some cylinders turned off due to multiple misfires happening. So, I guess, high octane gas does damage to lower octane rated cars? I have already filled my car with 95 gas, but there is still some 100 gas in the tank. The engine also started making squeaking noise after that highway ride. The noise is almost like when a generator belt gets wet and misses the gears, but not as loud and very constant. Can I do something to fix the overheating? Does the noise go away over time as the engine cools down and stops getting 100 fuel? I'm really worried. My car already has 220000 km of mileage (kilometrage, sorry!) and the engine was damaged by extreme overheating once (when the radiator leaked, all my coolant went away and my engine was running with no coolant for 15 minutes of high speed driving on the highway). It had the same squeaking noise after running like that, but in the end it stabilized, the noise went away and happy end! Don't know about this time, though... Thanks in advance, Aleksandr from Podolsk, Russia! | |||||
| Answer to: 2012 Acura TL purchase question | 33Relevance | 3 years ago | Hixster | Submit Your Question HERE | |
| From page 468 of the owners manual: "Your vehicle is designed to operate on premium unleaded gasoline with a pump octane of 91 or higher. If this octane grade is unavailable, regular unleaded gasoline with a pump octane of 87 or higher may be used temporarily. The use of regular unleaded gasoline can cause metallic knocking noises in the engine and will result in decreased engine performance. The long-term use of regular-grade gasoline can lead to engine damage. You may hear a knocking noise from the engine if you drive the vehicle at low engine speed (below about 1,000 rpm) in a higher gear. To stop this, raise the engine speed by shifting to a lower gear." This is probably where the 'only premium' claim comes from. The important thing to notice is 91 octane is 'recommended' but not 'required'. If it said 'required' then the answer would be "no". Using gas with a lower octane rating won't hurt the car's engine. Yes, your gas mileage will suffer, but not enough to offset the high price of premium gas. You can dl the manual here: | |||||
| Premium octane gas | 29Relevance | 4 years ago | Francesco Savanti | Submit Your Question HERE | |
| Hi Scotty, You mentioned that today's cars will run fine on 89 or 93 octane but engines that are recommended to use premium fuel will have less pick-up. Is it true that premium octane fuel burns cleaner than the low octane and will keep things from getting gunked up? Francesco | |||||
| Answer to: Octane Booster | 29Relevance | 5 years ago | Whatchamacallit | Submit Your Question HERE | |
| See below: | |||||
| Answer to: Can I switch to a different gasoline octane number? | 29Relevance | 5 years ago | Whatchamacallit | Submit Your Question HERE | |
| It says in the owner’s manual: “Select octane Rating 87 or higher. Use of unleaded fuel with an octane Rating lower than 87 may result in engine knocking. Persistent knocking can lead to engine damage.” So you are fine using 87 octane. | |||||
| Octane boost vs premium gas | 29Relevance | 5 years ago | RonnyR | Submit Your Question HERE | |
| Ok I just bought a used 2018 Lincoln MKZ black label. Its a 3.0 turbo charged engine. It states it take the premium gas 93 octane i believe. I filled up and it cost me $68 for a full tank. If I put regular gas 89 octane I believe and add a bottle of octane boost from say Walmart for $1-2 it would save me almost $15 per tank. It it safe to do this? | |||||
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