Hey guys. Got a question.

I had the only RX8 in town until a young kid in high school got one a few months ago. Since I am the only other 8 in town he comes to me whenever he has questions.

Anyways, he just called me and said his dad filled his tank with E-85 and wanted to know if that would hurt it. He's already ran 1/4 of tank through. I told him that is bad and that he shouldn't drive it until he gets that gas out of there and runs some fresh 93 octane through it.

First of all, am I right by telling him this?

And second, what is the process that needs to be done to get it out? I told him I will help him with it this weekend, but this is a new one for me and I don't know where to start for him.

Any advice would be appreciated. Thanks.


Also, he was already coming out this weekend for me to help him because he had a CEL P0171, running lean code. When I listened to his engine it was an obvious vacuum leak (you could hear suction sound) and we were gonna try to track it down as well.

Could these be related?

 

Id imagine E85 would need a lot of premix to work without harm given how dry it is. Also, if there is a lot of carbon the E85 will solvent clean this possible breaking loose debris large enough to pose a a problem. Ive used it quite extensively in piston engines as cheap race gas but even then I premixed as I was intructed to do. If it were me Id get it out too.

 

First, tell him his dad is an idiot. I'm pretty sure a factory engine can't run e85. It's much more harsh on seals and gaskets. It's like running av gas through a regular engine will make the piston rings very brittle. Except, we have apex seals which already break pretty easy. And trust me on the av gas. I blew an ae86 that way

 

Disconnect the fuel line, jump the fuel pump.

 

Lol, I agree on the idiot part. But how do I get it out? I tried searching and cant any info on how to drain the gas.

I havent ever had the pump out, so not sure about this idea.....but can I pull out the fuel pump, then stick a siphon pump in there and pump out all of the gas?

And what should I run through the lines to clean it out?

And also, I have some zoom cleaner that I was gonna run through it, will this be good enough?

 

That may work. How do I jump it? Just run it to the battery directly?

 

I presume that code began after the E85 fillup?

Makes sense, since alcohol has much less energy per gallon than gas, so if the injection system is not set up to enrich the mixture it will run lean. Running that lean is not good for any engine.

Definitely drain the E85 out before driving any more. If you do it by jumping the fuel pump, have a couple of gallons of gas on hand to finish the flush and drive to a gas station for a fill-up. Yes - run a wire from the battery to the pump. I used to do that on my VW rabbit when the wiring harness failed. Be very careful handling the gas and the electricity.

Good luck getting rid of the drained E85. Maybe your friend could put it in his dad's car.

Ken

 

 

wow, simply wow.

Anybody got that facepalm pic that I can use ?

 

There is a fuel pump circuit in the fuse box that you can jump. It's usually used to pressure test.

 

Well, a bit of an update.

The kid called me today, and I guess they went and talked to Mazda today. Mazda told them that it wouldnt hurt anything if they only did it once....and then went on to tell them that its ok to use E-85 for more performance as long as you mix it: 70% premium/ 30% E-85.

This sounds like B.S. to me....but who knows.

 

Hahaha. That's great!

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I don't know if the RX-8 has a filler tube restriction, but I think you can theoretically use a bilge pump to suck it out.

A ghetto way to suck gas out is to do it like a third world gas thief. You only need a container and a garden hose. Insert hose into the fuel tank via filler tube. Suck on the hose being careful not to swallow gasoline. Once the pressure differential in the hose is higher than at the opening end of the hose, it will flow out. Change elevation of hose opening to control flow (lower hose opening to increase flow and raise it to decrease flow). If you raise it too high, you'll lose the flow, in which case, you'll have to suck again.

 

70% -30% sounds like it might work but lot of good that'll do if you filled it up with e85. I think the kid should drain the e85 completely. And if he for some stupid reason decides to drive it, premix the HELL out of it.

 

That's usually not possible on modern cars - too much plumbing between the filler neck and the tank.

But if you're in a situation where you can siphon, a garden hose is usually too big in diameter. Also too long. And too opaque. Get a few feet of clear plastic tubing, maybe 3/8 inch. Make sure the tube has a foot or two drop below your mouth and the filler neck. Then you can see when the gas starts to flow, with lots of time to get the tube out of your mouth.

When you suck, do it with your mouth and cheeks, not by inhaling.

Auto parts stores (even in the first world) used to sell siphon hoses. Just a piece of tubing with a simple squeeze pump in the middle, no mouth action needed.

Ken

 

Get what you can out of the tank, drop some 2cy with a jerry can of fuel to get the car to the gas station.
I have put some E-85 as premix to clean out my engine after a slow driving winter with positive results.

 

I usually add a couple of gallons of E85 every time I fill up along with a lot of premix. I've never had any problems stem from the gas I use. I have been doing this for about 60,000 miles and my car is at about 110k miles right now, still on engine number 1 and its showing healthy compression numbers.

As far as filling the whole tank with e85, that might be a problem, but I doubt doing it one time will be a problem. I would just keep filling it up with 93 octane and eventually it will just mix out the E85 that is still in the gas tank.

 

I openned this up while laughing hysterically, only to find that E-85 is the new Seafoam!? Its harsh on soft parts (gaskets and hoses) so my main concern is the effect on the area between the plates and rotor housings. Even so, it shouldn't be too bad as long as the motor isnt flooded often. Can anyone validate this train of thought?

 

As stated the E will not hurt the motor one bit. It will however run lean as you will need roughly 30% more E-85 compared to gasoline. It should not hurt anything on the car as it has the plastic fuel lines. If they were rubber fuel lines the E would eat at them. All should be fine. I am running E on several high HP rotaries as its cheap race gas.

 

was thinking a clear hose/tube through the gas cap myself... that's how I used to steal...err...borrow gas from my parents as a kid...

 

No no no no no no no....NO!

Putting E-85 into a car that cannot alter the tune for it will most likely result in engine damage.

Do NOT mix E-85 with regular gasoline under any circumstances. The stoichiometric properties of E-85 are vastly different than normal gasoline.

Your best bet is to pump out the e-85 in the tank and get 91 or 93 octane in it.

 

I reread my post and it sounds as though I was saying to run it on E which I am not. I was saying you should not have damage from a little bit of E, but get it out of there.

 

Thanks to Flashwing and Rip-it for making that clear. I'll stick to seafoam.