cyberdyne

Hi All!

I recently traded in my W204 2012 C300 4Matic Sport sedan for a W205 2018 C43 AMG sedan and I am absolutely in love with it.

One thing that I do miss from the C300 though, it was able to run E85 which has a significantly lower price at the pump.
I don't see this capability listed in the owners manual or on the gas cap/gas door decal of my C43 AMG so I have not tried it.

Does anyone here have any experience with using E85 in their C43? It is something that is supported without any aftermarket modifications or is it a no-go?

C43HeartBoost

No, you cannot run straight e85 in a stock c43. You can run up to about e30 (blending 91+ octane with a few gallons of e85). I have been running such a blend in my stage 2 tuned c43 for approximately 2 years without issue. To go any higher than e30 you will need a new high pressure and low pressure fuel pump and a tune for proper operation. I am not aware of anyone on this board running above about e50 with this setup.

cyberdyne

Thanks for the great reply! I’ll stick with the 94 octane 0% ethanol stuff.

itsjustjake

I have a stage 2 from eurocharged too, do i need to ask them for a new tune to run a few gallons of e85 or can i just throw some in and see a difference in my butt dyno?

they’re closed today so i can’t call and ask till Monday

C43HeartBoost

You can, but it depends on how taxed the HPFP is with the stage 2 tune you currently have. If it was already running lean on the top end with 91/93 pump gas, it will be further leaned out with an e85 mix. The only sure fire way to tell is if you have a wideband air/fuel gauge (like AEM) or a dyno session. My advice is to hold off until you have discussed the issue with your tuner.

itsjustjake

great to hear! Coincidentally we ran 3 dyno pulls while doing the stage 2 tune so I’ll ask about the hpfp. Thanks for the info!

C43pleasehelp

who did u get the stage 2 tune from ? If I get a stage 2 tune can I get a map for 93 octane even tho I’m in California and mix with 91 and e85 to make e30 like u said ? And what’s ur 0-60 times after the stage 2 and running e30? Thanks g

Freder8d

https://mbworld.org/forums/c450-c43-...llons-e85.html

Edisonalikaj

Can I run any sort of ethanol on a stock c450’s fuel pump maybe like e30 without anything going wrong if I’m stage 2+?

C43HeartBoost

Your question has already been answered in this thread, as well as the thread linked just a few posts above your post.