E85, Injector Gunk & Seafoam.
 

To All:

Thought I would post this since there has been some discussions about E85, and the black gunk stuff that builds up on the ends of the injector tips..

This weekend I did a lot of checks on the car, as well as do a few modifications to my fuel system as I am having a hard time with fuel delivery on a single Walbro 255, FIC 1050's and a maxed out IX Turbo. The fueling issues developed over time, so I had a feeling that something else was taking place, rather than a single part not being up to the task immediately.

Some background/information on the motor:

2.0 Built ~9.8:1 Compression
Single Walbro 255 (GSS342)
FIC 1050 Injectors
Perrin Fuel Rail
FPR (Bolts to Fuel Rail, Don't recall who's it is)
All Stock Fuel Lines
~32psi spikes to 24.5 redline on a IX Turbo (Hallman MBC)
Injector duty cycles are climbing higher and higher over time. (?)


I pulled the pump assembly, smacked in the pressure regulating valve thing in the Walbro, moved the battery to the trunk, re-wired the pump on its own relay, pulled the injectors out all to have a look see as I will this weekend be traveling with the car up to NY from Charleston. Over time the car has been running more and more lean, as if the pump wasn't able to keep up really anymore. I was starting to get sputtering and backfiring as the car was leaning out under heavy loads/boost, so I decided to try and see what was going on inside the fuel system. (Plus, I have a complete fuel system going in the car later, so I wanted to prep it for the full install. (Fullblown twin pump, Fuel Lab filter, Fuel Lab pressure regulator, all new lines converted to AN fittings, -8 feed and -6 return and am going to run both pumps all the time..)

Now, onto the pictures. I pulled my FIC 1050's and that's what I found. Now, the car has had only ~4,500 miles put on it since I completely redid the motor. The car has been on e85 for almost two years now, but this is the first I have seen this really start to get this bad. Prior to building the motor, the injector tips never did this.

Onto the cleaning; I tried several things, and Seafoam tore through that black stuff like it was nothing. So, I decided to continue using it. I must admit, I am kind of inclined to put some in the tank from time to time seeing as how good it was at removing the stuff. Simply setting the injectors in the Seafoam for about 15 minutes made the mess in the cut off bottle as shown in the picture. I am very curious as to what the tops of the valves look like now due to the buildup at the injector tips. I wish I could somehow see them without removing the manifold. (Anyone have any ideas?) I took a picture where you can see about 1/4" into the injector bosses on the manifold though.

The Pump; everything looked ok here, nothing out of the ordinary. Pump has seen everything from 110 leaded, C16, E85, 93-87 from all different gas stations. The pumps life was mostly spent on 93 & E85 with E85 edging out 93 now.

The FPR; Something is wrong in there, I tried adjusting the screw as I noticed the pressure was a touch higher than I wanted it, and I moved the screw all around to no avail. Pressure did not budge at all no matter what I did with the adjusting screw. I do remember while rebuilding the motor, I initially redid the fuel system and found my FPR was all caked white inside (It's aluminum) to the point I was surprised it was still somewhat working. I am going to pull it probably tonight and see what I find. (Ran out of time last night) I will take pictures of what I find and post them here.

Anyhow, I wanted to put this together just to get some information out there. This in no way should be taken that there is evidence of a problem with everyone's set-up's, this is only to show you guys what is happening with MY particular set-up. You might find the same, you might not.

So, lets discuss...

Any ideas as to what that gunk is now that you've seen it first hand?

I am almost wondering if it is a sugary substance. Being a sugar based alcohol, could that be a sugary residual substance? I couldn't tell by looking at it. It still smelled like E85 does when your filling up.

Should I taste it next time I pull them out? :D

Maybe best to have the injectors professionally cleaned by someone like RC Engineering or similar service?

http://www.rceng.com/Fuel-Injector-C...XATul75zzEWdZO

That looks similar to the gunk I mentioned in the other thread, which several people have confirmed is actually in the fuel at their local station, rather than being a byproduct or reaction.

One quick question: what base fuel pressure are you running (you mentioned it was higher than what you were wanting)? Some folks on another forum running relatively low base fuel pressure (35psi or so) seem to be badly afflicted with the problem, while those running stock or higher pressures are seeing quite a bit less build-up.

(And then there's folks in other regions who aren't seeing any build-up at all, suggesting it's a regional supply problem. I know I haven't seen any evidence of a problem with a handful of cars here in Illinois, for example.)

Apparently some strains of E85 have something precipitating out of them. I think it is something some manufactures are adding to the fuel.

As for the fueling issues. Leaning out over time is usually the filter. Also E85 can damage some FPR's, especially lower grade ones that don't have a high quality diaphragm and internals in them.

EDIT:

VeraSun E85 is gunk build-up free for me on any injector (FIC, PTE, Bosch etc....). However VeraSun I think is bankrupt and will have new management so that may change.

It would be somewhat interesting to do a scientific test on them for sugar and starch.

The starch test is really simple you just dissolve the material into a test tube with water. Add a drop or two of iodine and if starch is present it would turn very dark colored a kind of blue black solution. Normally the water would be a light brown/organge color.

Sugar tests require a solution like benedicts solution to properly test for the presence of sugar. Again test is preformed in a test tube with substance dissolved in water. Add 2 drops of benedicts reagent and heat the water with anything really. If the solution turns any color it has sugar in it typically it will range from weak orange to a strong green.

I understand benedicts solution is a little hard to get so i suggest using a diabetics sugar test for urine, Clinitest Reagent Tablets. The tablets will react the same way as the benedicts reagent and show very similiar results with perhaps not a great a range for testing sugar. See this pdf for how it works.

http://www.vinquiry.com/pdf/Clinites...gSugar2001.pdf

Wow, those looked bad. I haven't had this issue yet, hopefully I won't have to deal with it either. I used to use Seafoam every so often in the past that may have kept everything squeaky clean.

Interesting, is your car sitting for a long time? E85 isnt a stable compound and has tendency to build up a varnish--which looks like what you have.. Just a thought.

I had thought for a while that it might have been "something" plugging up with gunk, but the only evidence I found of "gunk" was at the injector tips. I am very suspect that my FPR is the next culprit I am going to find later tonight. It will be at least a few weeks before I run E85 again as I am going on my trip this weekend, and am not going to try and run E85 the entire trip.

One thing I did notice is that my idle did get slightly better after my cleaning. Another thing was that I did not notice anything in the other ends of the injectors, in the screen area.

Another thing is that I am running my idle PSI at ~43 psi, about 10 psi more than stock. I was testing this out to see if it made low rpm/idling better.

I am suspect of the quality of the E85 at this station as it is the only station within about a 25 mile drive one way. Fortunately this station is about 1.5 miles from my work, so it is easy for me to manage. With only one station selling it here, who knows what is going on with their E85..

The car never sits for more than 12 hours at a time. The longest a tank has ever lasted me was around a week and a half.

Based on your explanation, it sounds like your FPR is the culprit. Aluminum isn't compatible with ethanol and corrosion will occur.

Perhaps it's just a product of the combustion then, with whatever additive may be in your supply of fuel.

Or, perhaps little corrosion particles, perhaps from the FPR, circulate through the system and do clog the fuel filters, but more ona microscopic level that is harder to see?

Filter clogging is major reason for going lean. This is a huge problem in with early DSM converts. Most are having change the filter 3-4 times over the first 5 tankfuls. The E85 is cleaning all the gunk out of gas tanks. leaves them squeeky clean. Not a big deal as filter only cost 15 bucks. Problem for EVO crew is factory filter is inside the stock fuel pick-up assembly. very expensive to replace as it cant be bought separately.

Not likely to be FPR. raw al may react with ethanol pretty quick, but anodized al is not affected by ethanol at all. I had al fuel filter sitting E99 for an entire year. came out looking brand new.

Odd

I just put some bosch injectors in this past weekend and was puzzled by the same thing. Weird Black sticky buildup on the tips. Odd part was it only happened to cyl 1-2-3. 4 was completely clean. Ill post pics when I come back home from Canada on friday.

I noticed a degradation of engine idle quality and general engine response over time (buildup I guess). I put the bosch's in and its much much much better now. Idle is so nice!

If the junk is on the injector tips, where else is it collecting?

FWIW I am running stock fuel press. 43.5psig with vac hose off the regulator.