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One of my friends had to buy a new (to him) car out of necessity. He decided to buy the only new car on the lot. He was bragging. Great deal. Here’s the catch.
by shotta 4y ago
One of my friends had to buy a new (to him) car out of necessity. He decided to buy the only new car on the lot. He was bragging. Great deal.
Here’s the catch.. it requires premium. He didn’t know that. The dealer made sure not to volunteer any extra info. He’s keeping those miles low.
- edmcnulty101 4y agoThe car requires premium gasoline? Is that a thing? edit: Thanks for the info. Did not know that. I've always had piece of shit cars that could probably run on McDonald's french fry oil. :)
- burnt_toast 4y agoYup, some engine's are designed for it. Usually for performance reasons if the engine is boosted or high compression.
- bovermyer 4y agoSome engines require higher octane gasoline, yes. You can use lower octane in it, but you're going to hurt the engine.
- sonofhans 4y agoIt’s been a thing. My car is 20 years old and requires it. Engines with higher compression require higher octane fuel to reduce pre-detonation and pinging. Using low-octane fuel in one of them can cause game-ending physical damage to the engine. Many more modern cars can sense lower-octane fuel and adjust for it, at the cost of power and efficiency (i.e., mileage).
- kelseyfrog 4y agoYes, I have a car which requires premium gasoline. Though I haven't tried putting in regular, my understanding is that doing so would induce knocking.
- Sebb767 4y agoA car with knock sensor will detect lower-quality fuel and pull back timing. This will usually limit your power, but not damage your car. My car manual even explicitly states that it won't affect engine lifetime. Full disclosure, I still use premium anyway because I want to keep the car for a long time and I don't fully believe this disclaimer.
- camhenlin 4y agoGenerally you'll get worse fuel economy due to the ECU and knock sensor detecting the lower grade fuel and pulling ignition timing out. It's unlikely you'd even save money at the pump
- zdragnar 4y agoThe octane rating you see on gas indicates the pressure at which gasoline will combust. Engines tuned to a higher compression to ignite require higher octane level gasoline. Using something other than what the engine is tuned to might put a lot of extra wear or degrade performance of the engine.
- datavirtue 4y agoThe gasoline will ignite before it is supposed to, forcing the piston back down before it has travelled all the way to the top of it's stroke. The engine will destroy itself. You can hear "knocking" coming from the engine when this is happening. It's worse than it sounds.
- zdragnar 4y agoI know this is definitely true of older engines that aren't controlled by fancy software, but I suspect at least many consumer cars are capable of adjusting to the difference. I could be wildly wrong here though, and wouldn't want to test it myself.
- kube-system 4y agoKnock sensors are standard on every car made by a global automaker since the early 90s when fuel injection became universal
- dumptruk 4y agoSome vehicles, especially ones with OEM performance tuning, run high compression ratios or forced induction. Higher octane gas allows for more compression within the piston before ignition. I had a 2003 Toyota Matrix that redlined at 9100 rpm and used their fancy Toyota variant of VTEC that would dynamically swap the camshafts on the engines past a certain RPM. Although the engine was naturally aspirated (no turbo), it had the compression ratio of 11.5:1, which is pretty high for an economy vehicle (1.8L)
- jakear 4y agoAll the comments are giving unequivocal yes’s, I’ll note that some cars (my buddy’s Subaru) will say they require premium but work just fine without. Currently going 240k miles still strong.
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- fragmede 4y agoIn case you're being facetious, old Mercedes diesel cars can literally run in old MacDonalds french fry oil with a tiny bit of modification.
- deleted 4y ago[deleted]
- pc86 4y agoI like how you say "the dealer made sure not to volunteer any extra info" as if this was a secret and the dealer somehow scammed your friend into buying a brand new car at the height of a chip shortage and record high car prices. The lifetime difference of premium gas financially is next to nothing.