I would be curious to see how the affects would differ between different motor oils...synthetic, etc.

I don't know if I have the problem or not, but I have been running E85 for a few years now, both in IL and CA. I don't show any symptoms that would clue me into the issue of deposits on the injectors, but every once in a while (a couple times a year) I run a tank of 93 to be sure it's clean.

It may simply be dependent on the amount of blow-by per car and the type of motor oil. I personally run Amsoil SSO-0W30 and have very little blow-by.

 

Pulled out my FIC1050s last night to replace all the seals and rings. They are all sparkling clean and no sign of black gunk at all.
Been on E85 for 4 yrs but switches back to 92 for winter and for a tank or two mid summer because I'm worried about this gunk issue.
Car has been on E85 the last 3 months prior to pulling the injectors.
E85 is from gas stations in the KC area.

 

^^^Youve got the correct recipe. Flush w/gas periodically

 

Has there been similiar cleaning success with the "E85 specific" injector cleaners? I'd prefer to keep E85 running all the time and would rather running bottles of these along with them.

 

Im not sure myself but our expert poster arghx7 noted this pasted here:


Using Fuel additives and Normal Gasoline blends

There are a lot of fuel additive blends out there and they change all the time so I can't speak for all of the various formulations. What we do know based on GM's research is that PolyEther Amine or "PEA" , which can/used to be found in Techron products, cleans valve deposits but does not clean injectors with this problem. In fact, too much of fuel system cleaner could make the problem worse.

Go back to page 9 & read his findings on the exact causes & cures

 

My assumption is the carbon buildup over time being flushed through the system, if you think about it we have been putting miles on our cars with 93octane until recently we discovered e85 lol. its probably the fuel system cleaning itself. Its probably going to take a awhile until the system gets clean

 

Go to post #130 & read the most comprehensive explanation to date

 

yea I saw that earlier, just forgot to edit my post

thanks

 

so run 93 to clean out the fuel system if using e85. got it

 

Here's my take on the deposits.

What are they?
PIB

Where do they come from?
PIBSI - A detergent in all oil.

Why does PIBSI convert to PIB on e85 and not gas?
Likely because of the polarity of e85. Gas is non-polar.

 

How is the oil getting to the injectors - PCV?

 

Please read post no. 130

 

Please read the GM data that post #130 is attempting to paraphrase. Because you obviously didn't, I'm going to quote directly from it.

"These findings, together with the result that the reduced PIB E85 caused the same, or even worse, deposit problems, caused abandonment of the PIB-free E85 idea."

"Additives from both suppliers showed clean up effect on inlet channels and valves, but no effect on injectors."

GM abandoned the PIB free e85 idea because it had no positive effect on the result. Furthermore, they concluded fuel additives had no result on injector deposit formation.

The only thing that GM truly shared in that article were:
1. Vehicles in traffic are more prone to the issue.
2. Reducled PIB levels in e85 does not reduce the formation of injector deposits.

Yes, mfred. I would venture to say it has something to do with the PCV {thumb up}.

From the GM data quoted in post #130:
"The PCV systems did not need any modifications for the BioPower variant."
They never touched it.

But GM sure cares about the PCV system on the new flex fuel turbo motors. See the PCV passages in the new flex fuel blocks?

If fuel is the source of the rubber, someone please explain to me why a car in vacuum consuming much less fuel is more prone to the issue?

-James

 

^^^If ARGHX7's post is accurate, & I believe it is, this is the simple summary of the mechanism that is causing the black tar substance
Since this post, I now flush my system w/a few tank fulls of 91

Been on E85 for over 5 years, Im satisfied w/the explanation

 

I'm sure there are no concrete answers, but I will mention that when I had my Evo in the Tri-Cities, I had zero gunk build-up even after a full year of continuous E85 that was consistently measuring out at 72% ethanol. I was on the stock PCV system at the time. Within six months of moving my Evo to Portland and a completely different brand of E85, I started experiencing rough cold starts, and not unexpectedly, the injectors had become gunked up.

I recently switched to a crankcase ventilation system that does not use the intake manifold for PCV, so I should pull my injectors, document, clean, and reinstall.