Has anyone tried E85?

[Pazza]

Googling around doesn't really give me information about people trying E85 in the CTHE engine. VW didn't mention anything about a flex sensor.

Anyone tried the corn juice?

[brad]

I have in a 1.8tsi. It will give the power & torque a noticable kick, but...

The VW o2 sensor, ECU & map aren't up to the task. So the ECU overfuels because of the high o2 content of the burn and the engine runs rich. Eventually you will get a coating of soot all over your 02 sensor which will cause poor fuel economy.

Every time you give the car a squirt you'll wonder if you're maxing out the injectors.

Unless you are willing to do it properly and log mixtures etc & get an E85 remap you'll not know if you are doing good or harm.

Maybe run 98 with a top up of E85 to make E10 or E20 or just buy 100ron E10 from Liberty. You will notice it

[wai]

The other thing to consider is the fuel system itself. It needs to be able to handle the high ethanol content.

Ethanol contains oxygen atoms and when the ethanol burns, this oxygen is released. The ECU will try and compensate, but may not do it too well.

[Hail22]

Simply put:

[Pazza]

So that's a no?

[nomadx38]

No - just a straight out no. The system isn't designed for it and it says that it cannot be used in the manual (well 1.2tsi anyway)

Not to mention as the other guy said you without a tune it will do more damage than good. Ethanol has a higher O2 content and with stock tunes will usually lean out the AFR which causes high temps in the head which is where ethanol does most of the damage to the valve seats. The advantages of ethanol is the higher flashpoint which allows a higher compression ratio (or higher boost) without pre detonation which helps to combat ethanols lack of energy compared to petrol. Just stick with 98

[Transporter]

When the petrol containing even small amount of ethanol comes in contact with water of any form, liquid or just as humidity the ethanol will absorb it and once it reaches a saturation point, the ethanol and water will phase separate - forming 2 or 3 layers in the tank. So, you will have an upper layer of petrol, than layer of ethanol and water or the worst (it's also common) a third layer of water only. The consequences of that are often catastrophic for the engine.

The ethanol is a very aggressive solvent and will attack gaskets, O-rings and rubber hoses. Those who don't use their cars every day are even worst of, since the deterioration is the worst while the car is standing (you go on holiday or otherwise don't use the car for a few weeks).
The fuel system components made of certain type of plastics will become soft or hard and brittle, brass, aluminium and copper will oxidise to the point of failure.

It's okay to use the ethanol in the racing cars, because the racing car engines very often need to last only the length of the race plus one more lap.

[Pazza]

I was thinking that with the newer engine technology they may have made an allowance for ethanol based fuels.

Dinosaur juice it is.

[amazeer]

So long as the car is tuned to run on it without leaning out it is fine. My car club has heaps of members that run it in occasional use cars. Brasillians have been using it for a long long time. One of the commodores is e85 capable. Not polo though.

[brad]

No - just a straight out no. The system isn't designed for it and it says that it cannot be used in the manual (well 1.2tsi anyway)

Not to mention as the other guy said you without a tune it will do more damage than good. Ethanol has a higher O2 content and with stock tunes will usually lean out the AFR which causes high temps in the head which is where ethanol does most of the damage to the valve seats. The advantages of ethanol is the higher flashpoint which allows a higher compression ratio (or higher boost) without pre detonation which helps to combat ethanols lack of energy compared to petrol. Just stick with 98

ethanol burns really cool so combustion temps aren't a huge issue.

It's still a no unless you do the right tune.

I have a mate that does a lot of tuning on Subarus with E85. It's quite brilliant stuff if you do it right.