Low quality fuel issue
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Newbie
Joined: Oct 2025
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Low quality fuel issue
Hi guys, I had a fuelling issue recently with my W204 C63 2010 and I had some issue regarding knocking due to low quality octane. My question is how do I prevent this from happening in the future since my country doesn’t have the best octane quality. Should I be using octane boosters or adding a litre of ethanol on every full tank of gas? Or any other tips if you guys have. Thanks
Member
Joined: Feb 2008
Posts: 101
Likes: 5
From: Rivers, Manitoba, Canada
2009 Mercedes C63 AMG, 2013 Mercedes C350 4Matic Coupe. 2012 GLK 350 4Matic
Where do you live?
Hi guys, I had a fuelling issue recently with my W204 C63 2010 and I had some issue regarding knocking due to low quality octane. My question is how do I prevent this from happening in the future since my country doesn’t have the best octane quality. Should I be using octane boosters or adding a litre of ethanol on every full tank of gas? Or any other tips if you guys have. Thanks
Junior Member
Joined: Jul 2018
Posts: 20
Likes: 6
From: Johns Creek, GA
2010 E63; 2017 GLC300; 2000 BMW 323i, 2020 GLS450
Top Tier seems to work
Agree. I stick with Top Tier brands and have only once had trouble in my E63. Usually run QuickTrip. Always premium. Not sure if this helps you if you are outside the US or Canada.
Out Of Control!!
Joined: Jun 2004
Posts: 13,799
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2014 E63S; AMS 100 octane ECU dyno tune; EDOK TCU tune; BB intakes; sprintbooster
how do you know you're knocking was associated with bad fuel?
You can add a gallon or so of E 85 to increase the overall octane to a nearly full tank of your 91+ octane fuel
You can add a gallon or so of E 85 to increase the overall octane to a nearly full tank of your 91+ octane fuel
Last edited by PeterUbers; Nov 8, 2025 at 06:11 PM.
