Gas
#5
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Nissan GT-R BE / '12 Ducati-1199 Panigale S / '12 C300-4M Loaded/GLK350-4M Loaded
No it's not engine size, it's usually the compression/ratio and or turbo configuration that does. Most if not ALL MB gasoline engines require premium fuel. The higher the better. High Octane (H.O.) fuels delay their combustion thus allowing the piston to reach its full compression range, thus enabling the engine to take full advantage of the power stroke it produces. Lower Octane fuels (L.O.) burn and combust quicker (earlier) and at much lower compression and pressures, thus they're perfect for lower compression ratio engines but will pre-ignite too soon (pre detonation) during the compression stroke if used in high compression or turbo engines that require H.O. fuels.
Last edited by MBRedux; 06-24-2012 at 06:37 PM.
#6
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No not size, it's usually the compression/ratio and or turbo configurations do. Most if not ALL MB gasoline engines require premium fuel. The higher the better. High Octane (H.O.) fuels delay their combustion thus allowing the piston to reach it's full compression range, thus enabling the engine to take full advantage of the power stroke it produces. Lower Octane fuels (L.O.) burn and combust quicker (earlier) and at much lower compression and pressures, thus they're perfect for lower compression ratio engines but will pre-ignite too soon (pre detonation) during the compression stroke if used in high compression or turbo engines that require H.O. fuels.
#7
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Always 91, mostly at Costco.
Knock sensor takes care of lower octane if it's not too low although I don't know what is too low.
Knock sensor takes care of lower octane if it's not too low although I don't know what is too low.
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'08 Mercedes C300
#10
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I will ask service advisor about that.
When I took delivery, my saleman filled in with regular gas. He said it would not hurt. That was the only time with regular, I think is 87. There is no 93 around me, always 87, 89 and 91.
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Nissan GT-R BE / '12 Ducati-1199 Panigale S / '12 C300-4M Loaded/GLK350-4M Loaded
You need to ensure that you use high enough to meet the recommendation. Higher the octane the more corrosive (not sure if that's the right word...) so you don't want to go higher than is necessary. Definitely don't want to go lower though because of pre-detonation as you've mentioned.
https://mbworld.org/forums/glk-class...ate-alert.html
#12
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Correct! Here's something that might interest you all.
https://mbworld.org/forums/glk-class...ate-alert.html
https://mbworld.org/forums/glk-class...ate-alert.html
#13
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2009 c350 arctic White pano. MM HK
im using 95 oct and i hear knocking some times i send the car to the delar and he seed nothing wrong and the knocking and bad small stile there ?? i did every thing without success
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Nissan GT-R BE / '12 Ducati-1199 Panigale S / '12 C300-4M Loaded/GLK350-4M Loaded
I notice the picture that your referenced post points to calls out RON rating. My C350's fuel door sticker doesn't mention the rating test. It does say 91, but doesn't say RON/MON/AKI. I'm assuming that all US pumps use AKI? I know that the pumps in Pennsylvania that I've been at use AKI.