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I put unleaded in my TDI.....

ChrisUK

Eat My Smoke
Oct 20, 2004
2,258
0
Liverpool, UK
I was having a bit of a mare yesterday, & due to filling up with unleaded on my bike, I started filling up my MK1 Leon TDI with unleaded !!!

I out about £4.50 in (the only reason I even noticed at 1st was the price, I thought to myself that the diesel was cheap....)

Few calls later, I pushed it over to the diesel pump, and managed to get £45 worth of diesel in it.

Car seems fine, just taking it easy until I can get a few tanks of diesel through it.......


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Bizz

Feeling the extra power
Apr 4, 2006
70
0
Darlington/Norwich
Unlucky chap, but youll probably find once the unleaded has been through its system and is running on 100% diesel she'll be running better than before.

A mate of mine filled his 170bhp diesel golf up with petrol and didnt notice until it spluttered to a halt. We drained the tank, changed the filters, etc, etc and now its running like a train!!!!
 

lc_allan

Northern Monkey
Sep 15, 2006
3,389
4
I'm sure I've read that if you've filled no more than 10% of the tank capacity you will be ok. Any more and your gonna have problems with seals, injectors etc... When you use half a tank brim it back up again to dilute it a bit more. Should be ok :redface:
 

The MoffMeister

Half Hoff, Half Moff.
Apr 4, 2006
2,937
0
colchester
my god what a dime bar haha

i remember aa man telling me you can do that to clean out engine etc sometimes and vice versa lucky you noticed it when you did my miss's mum filled up a range rover hse big thing with petrol to the top and it was a diesel cost £5000 or so...
 

Cupraloon

Guest
A bit of petrol in a diesel isn't too much of a probelm it's if you do it the other way you get problems, and potentally can get very expensive....

So don't put diesel in your lc/lcr, people... :doh::redface:
 

tom167

bucksvag.net
Mar 27, 2006
201
0
Milton Keynes
A bit of petrol in a diesel isn't too much of a probelm it's if you do it the other way you get problems, and potentally can get very expensive....

So don't put diesel in your lc/lcr, people... :doh::redface:

Thats wrong, putting diesel in a petrol isn't particulary harmful as its a lubricant, problem is putting petrol in a diesel because its NOT a lubricant. Diesels, particulary the high pressure pump, require the lubricating qualities of diesel fuel.
 

Tom B

Active Member
Apr 2, 2002
4,710
16
Northampton
Yes, tom167's right, putting petrol in a diesel is a bad idea. The diesel lubricates the fuel pump as it goes through, petrol starves it of lubrication and can kill the pump if its used for too long.

Remember that diesel is an oil and petrol is a liquid, so they will not mix together. Chances are the petrol is still in the tank, on top of the derv.

If it was my car, I'd get the tank drained and change the fuel filter.
 

tom167

bucksvag.net
Mar 27, 2006
201
0
Milton Keynes
Also, if you're paranoid enough you should check inside fuel filter for any metal filings. (open it in such a way as not to get inside though, ie chisel).
 

Cupraloon

Guest
Sorry matey i'm sure your wrong, i used to work in a main stealers where we had quite a few people do this ... you should probably read this, if you have a petrol car, and have put diesel in it by mistake

http://www.theaa.com/public_affairs/reports/aa_misfuelling_feb2007.pdf

And This...

What happens if I put petrol in the tank of my new diesel car?

Nothing good. If you put only a small amount of petrol into the tank then realise what you are doing and stop, and there is room to put a large amount of diesel in too, or the tank was already half full when you started putting in the petrol, don't worry. A diesel engine will run, albeit roughly, with a bit of petrol mixed in the fuel and not do any damage to the motor. If you have a high ratio of petrol to diesel you will have to drain the tank and refill it with pure diesel.

On the other hand, a little bit of diesel in your petrol tank is a major worry. Petrol is designed to be hard to ignite, the higher the octane rating the harder it is to make it explode just by heating it. Diesel on the other hand is made to burn or explode easily when subject to heat. So a little bit of diesel mixed with the petrol in your tank lowers the octane rating by a huge margin and your petrol engine will detonate, knock, and destroy itself in relatively quick time.

Taken from here --> http://carsguide.news.com.au/story/0,20384,20121692-5001701,00.html


http://news.bbc.co.uk/1/hi/uk/3476815.stm
 
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tom167

bucksvag.net
Mar 27, 2006
201
0
Milton Keynes
A modern diesel engine will not run with petrol in it, the high pressure pumps require constant lubrication from the diesel and without it the pump will either seize or loose compression.

Nope, sorry completely wrong, diesel will not ignite easily, i would gladly put a cigarette out in a puddle of diesel. It requires high compression and heat before diesel ignites. Putting diesel in a petrol will most likely jus make it a lil smokey.

I'm a mercedes benz comercial vehicle tech, i see petrol in diesels all the time, trust me lol.
 

Tom B

Active Member
Apr 2, 2002
4,710
16
Northampton
I am in the motor trade and have seen petrol in diesel cars so many times, the cars will usually break down within a few miles if its been brimmed. Its even funnier when the salesman does it! :D

The only time I've heard of people putting derv in a petrol is when I foolishly did it once in my Cordoba 2.0 16v, I drove the car 25 miles before I realised, the car was sluggish and smoked more than usual.

Petrol is designed to be hard to ignite, the higher the octane rating the harder it is to make it explode just by heating it. Diesel on the other hand is made to burn or explode easily when subject to heat.

If thats the case then why do failed F1 fuel stops end in flames? The fumes from petrol are highly flammable, derv has to be pressurised and heated before it can ignite. The higher the octane, the bigger the bang.
 
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Cupraloon

Guest
I'm a mercedes benz comercial vehicle tech, i see petrol in diesels all the time, trust me lol.

Fair enough, i conceed to your knowledge ;)

but at the end of the day it's going to be an expensive mistake, when i worked at a main stealers it was a very expensive mistake for the people that did it.

and i for one wouldn't in a million years put diesel in my petrol car just the clean it out as some have said just to help it run a bit cleaner ... that's madness.

I certainly would'nt recommend anyone else try it either,, theres a lot of misinformation on the net isn't there....
 

lc_allan

Northern Monkey
Sep 15, 2006
3,389
4
I thought it was physically impossible to put the Diesel nozzle into a petrol car now?. I have no idea as I've never used the Diesel pump :)
 

Cupraloon

Guest
yup the nozzles are a different size, doesn't stop people forcing them in tho' it seems, especially where i was working.... perhaps that says something about vauxhall owners tho' ;)
 

Tom B

Active Member
Apr 2, 2002
4,710
16
Northampton
People dont think about it when they go to the petrol station...my excuse was that I drove a TDI daily and the Cordy was my weekend car.

They've been campaigning to get the nozzles changed for years, its a great idea but its expensive to implement as all the worlds pumps and car fuel nozzles would have to be changed.
 
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