I've been having an issue on a local Evo 10 with some fuel delivery problems on E85 that we had kept chasing and couldn't quite get...

1. Fuel Relay OK
2. Upgraded Injectors
3. FuelLab AFPR (raised pressure no change)
4. Walboro in-tank pump...

This, as far as I know, was the first Evo 10 tuned on E85 in America. We tuned this back in March, on the stock turbo (it now has a Blouch Dominator 2) so it most likely has the most miles on E85 of any other, you can see the results here: https://www.evolutionm.net/forums/7044333-post55.html

Today it came back in after upgrading the underhood fuel lines, adding a upgraded fuel rail and a FuelLab AFPR. Still same issues.

I finally decided to take the pump out and check things out. Here is what I found:





Notice the orange OEM slinky fuel line. Guess what color they are in regular gasoline and stock? Semi-translucent white, like this:



The line was also sticky to the touch which I imagine is because it has been breaking down in the E85. The black slinky line was as well. (disregard the loose pump)

The fuel pump sock used was also the "walbro" kit cotton based sock which had all the cotton broken down and missing, which is probably now in the fuel pump and filter.

We will be replacing the slinky OEM line (which is pretty ghetto to begin with) with real fuel hose.

I *HIGHLY* recommend all Evo 10 E85 users to replace these lines with real fuel hose and do not use the cotton based fuel sock, but a Evo 8/9 OEM sock or some other non-cotton based one.

 

Have any other fuel additives been added by the owner that could have done this?

 

Straight E85 24/7

 

Wait.. is the Evo X designed from the factory to run E85?

 

No, it needs to be tuned for and have larger injectors and upgraded fuel pump to run E85, just like the Evo 8/9.

 

and apparently some lines and such.

Ethanol is NOT designed to be in these cars.

 

Yes apparently so, now we know.

E85 works just fine on Evo 8/9 for years now and many other non-OEM FlexFuel vehicles for years as well.

I've run E85 24/7 for more than a year now on my personal Evo 8. I even posted a thread awhile back about what my motor looked like when I opened it up a couple months ago.

 

Wow that is a good catch, I'm sure we'll have some other E85 users check their fuel pump assemblies and report back as well.

 

Mine has a sticker on the inside of the filer flap saying no ethanol based fuels. Thought is was full of s$%t but obviously not.

 

interesting!

nice find Bryan!

 

So the stock X fuel sock basically fragged and caused fuel delivery issues.

Good find Bryan!

Those are surely some funky hoses Mitsu used in the X.....lol

I know E-85 does seem to soften some plastics . Did the hoses look compromised other then sticky? I have noticed E-85 makes plastics softer and pliable not like gas that turns them brittle and stiff over the years. Haven't seen the plastic lines lose their integrity yet though.
Nevertheless it would be a worthy upgrade to replace them.

 

thanks !!! great to know!

 

Wow, that's not right. If e85 is doing that what happens when you run regular gas which can have up to 10% ethanol???

 

Something you might want to try is pull out a X pump that has seen nothing but gasoline also. Reason I suggest this is gasoline over time will discolor that fuel line also. I've had many of the Audi B5 & B6 A4 fuel pumps out replacing level senders and pumps and they all turn brown/orange like that over time and they are clear when new. The pump housing & pump look very similar to that setup. Not saying our cars are the same, but it would be nice to see a comparison just in case. Now the fuel sock is strange, those should never deteriorate. Just my .02.

 

Yea it would be nice to see what another gas only Evo 10 fuel pump assembly looks like. This was sticky to the touch however so I'm thinking it wasn't liking being in E85.