If Ethanol acts like a cleaning agent by itself and we are suspecting regular gas deposits to be the cause of the gunk buildup , why should we refill with "dirty" fuel?

But I'm suspecting it has something to do with either the PCV, EGR or both.

 

The gunk is due to additives and cleaning agents that are in the E-85. E-85 is, as you know 85% ethanol 15% 91-93octane. Sometimes the mixtures are made in house at the gas station and not at the local distributor. The additives that are added into the 91-93 octane are designed for regular heptane and long chain hydrocarbons and are not intended for use with ethanol. Unbeknownst to the gas station employees or sometimes the truck drivers that add the Ethanol to the tank on top of the gas, those additives can cause problems.

So, you have the E-85 polluted with a detergent that wasn't meant for its use and at the injector tip it can come out of solution and cause gunk buildups on the injector itself. It is likely that the additive forms a sticky film on the tip which collects the gunk from the lines and tank also. It is either that, or the detergent reacts with the gunk that the E-85 is pulling out of the lines/tank etc and instead of dissolving things it just keeps it at the particulate level and it doesn't make it into the fuel spray and collects on the metal injector tip.

This additive gunk is soluble in 93 octane or normal gasoline (which it was designed for), so if you have gunk build up on your injector (it is rare) then just run a normal tank of gas through it and it will dissolve and burn up in the cylinder. Personally I wouldn't want that being burned on my pistons as it could cause hot spots, so the best option is to clean them and switch where you get your E-85.

 

WTH, So there are gas stations that actually do in house additive mixing with E85 ?

Although I dont have very many miles put on, but since by now that I dont have any gunk build up on mine, is it safe for me to assume that the Shell gas station I get my E85 from is the better of the stations?

Any time frame of how long this buildup can accumulate if filled up with the "bad" E-85 mixture? I've heard and read people having issues just after 20 miles of driving etc...

 

There are some stations. Not sure it is distributor dependent or even chain dependent. Remote E-85 locations probably do their own tank mixing since distributors set up to mix specifically for E-85 are probably a far distance away.

Gunk buildup on some has taken thousands of miles, on others a few hundreds. There is no exact answer to this question. Just have a WBO2 and keep an eye on the AFR trends. If you notice you are starting to lean out a little bit, remember that gunk buildup could be a possibility.

I have been on E-85 constant now for almost two years and nearly 5,000 miles, I just pulled out my ID2000s to do a fuel rail and FPR setup and the tips were spotless. Its just the luck of the draw as to where you get your E-85 I guess.

 

Here is the thread which started the controversy, after which I did testing and the additive packages is what I found to be the most likely cause for the gunk.

https://www.evolutionm.net/forums/ev...0s-unreal.html

 

Thanks for the info.

I got the wideband, gonna keep my eye on it to see if there are any changes as time passes. I'll still pull the injectors randomly over time just to double check. And just use the same station for fill up.

 

Have run EGR both ways.

 

ttt

 

What information are you looking for? As stated, I am certain it has to do with the detergents used in the 93 octane that is mixed with ethanol to thin the mix out to E-85. Either the additives and solvents aren't soluble in the Ethanol and they form a film that catches debris on the injector tip, or the additives themselves continue to form a glob of sludge by merely not following the spray pattern of the ethanol.

I am not sure if this problem is linked to a single fuel distributor or ethanol plant supplier, but it does happen on occasion. I had to get my samples from a local guy since I have never had this problem, and I have been running E-85 through my ID2000s for just under a year and before that through my PTE 1200s for over a year with no issues.

Keep an eye on your WBO2 to see if you are leaning out unexpectedly on E-85, and realize that if you are this could be a problem. A quick fix is to just run a tank of 93 octane through the car and it will clean it out, but this is the lazy way as those gunky buildups could cause hot spots on the pistons and just dirty up the cylinder in general. The right way is to pull the injectors and clean then, they can be soaked in 93 octane and the sludge will come right off.

 

I believe I am suffering from this problem right now. Will be pulling the injectors this weekend to confirm. Only fill up at two stations. One more than the other. However the other has been more frequent than the one as of late. So I have my suspicions.

If confirmed I will post the gas station here. I am in the NW burbs of Chicago. Two signs. 1. Rough cold starts 2. WBO2 on WOT pulls has gone from a steady 12.0 AFR to redline in 3rd gear to 12.7ish.

 

sounds like you might be getting moisture/water in the tank. when e85 mixes with water it turns into a thick milky like substance.

 

Ever collect any of the fuel from the station nozzle in a clean glass jar?
-If so is the color ever so slight yellow OR pure water clear?
-Have you checked ethanol % to see if they made an error going to fall or winter blend and instead went to E98?

 

So the E85 station in Crystal Lake apparetly mixes in additives to their E*85. I am going to drive over there and ask them to be certain. Pulled the injectors and had ever so slight tar like subtance inside of the tips of the injectors. IT was slight but once cleaned, my AFR's richened up nicely. I am still however a little leaner than original tune. I was tuned in warm weather. I think I am now suffering from cold weather E85 atomization blues. ITs not significant but went from 12.0 WOT to 12.8 WOT before unclogging to now 12.3 12.4 ish.

 

That concerns me a little if they are adding additives- they better be the proper type or they will create the problem you are having.

 

I'm not sure all the Evo guys around here are getting E85 from the same station and some guys don't have issues and some do. I have cleaned mine before and cleaned them today as I took them out to sell them, there was some gunk on them. It wasn't bad. I don't think the station we use adds additives but I could be wrong. I know someone who works there so when I get my car back on the road this weekend if the guy I know is working I'm going to ask if they mix additives in.