Bio Fuels

The 200 Tdi will run on just about anything combustible, I'd be a bit careful with any vehicle with a cat or sensors in the exhaust but 5-10% bio oil should be OK. TonyB

I run a '95 300 TDI on biodiesel, only trouble i have is if I don't get the mixture right for the temperature. put topping up with a regular diesel soon sorts that out.

If you're having that sort of trouble with biodiesel I'd be looking for a new supplier as there should be no noticeable difference to dino-diesel. Or are you running SVO?

I reckon he is running straight vegetable oil (SVO) / dino diesel mix rather than a real bio-diesel. Real bio diesel should be virtually identical in performace to dino diesel.

When talking about bio-fuels one has to be very careful about the terms and words used, call things by what they are not some generic term like "bio-fuel", that refers to any fuel (solid, liquid or gas) derived from a renewable source, like raw timber, vegetable oils or shit.

And what are us petrol engined folks supposed to do.

Perhaps I should be distilling my own moonshine?

Yep, ethanol is fairly clsoe to petrol. I don't know if any tweaks have to be done to run on ethanol or not.

no, it's proper bio, not SVO, although I have ran that with Dino. the only issue was in the sudden cold snap a week ago. Bio can be tricky in colder weather.

Other than that ,18 months of hassle free fuel.

Huge carburettor jets - you need about twice the volume of alcohol compared to petrol for the same power output.

Thanks for the response so far.

Taking the two threads i.e diesel and petrol.

Diesel

I'm pretty confident that any of the TDi's will be OK but I'm wondering how a TD5 would cope.

Mixture wise on an older engine friends seem to get away with an 80/20 mix of home made to commercial fuel - again would a TD5?

Petrol

I own an V8 and ethanol is the only stuff I know of as an alternative to petrol.

You can go the LPG route which I would recommend (I've done it) but check out sources first. The South West (where I live) is great but London sucks. Plus don't do what I did and convert a card vehicle - no matter how often/frequently you run it on petrol things still dry out and stick. Injected versions seem fine.

How many modern cars have carburettors these days, virtually everything is injection. I guess then it is just a case of adjusting the ECU, assuming the injectors can handle the required fluid volume in the required time.

IIRC there's a bit of dickering with the lambda sensor needs doing too as stoichmetric on alcohol is different to petrol.

Is this home brew? Cheers Graham

Woz zat mean in English? Isn't the lambda sensor just measuring the level of oxygen in the exhaust thus it's reading just needs a different interpretation by the ECU. What dickering can you do to a sensor?

Yes, it compares the level of oxygen in the exhaust with the level of oxygen outside.

For alcohol it would have to feed the engine with about 70% more volume than petrol for a stoichiometric burn.

None apart from destroy it.

It would make a difference at a MOT test though, just as lpg does, because the ratio of CO2 to H20 changes and I think unburned hydrocarbons are calculated from this. That's why they use a correction when testing on LPG.

AJH