My yellow fuel reserve light had been on for a while this morning so I eventually filled up when I was shopping at my local tesco's later on. Shortly after leaving, my car was running like a pig and belching out smoke, I pulled over and had a good look around the car and in the engine compartment. I then checked my fuel receipt which said I'd filled up with 8 litres of diesel on pump number 8.

I managed to drive about a mile and a half to the garage where I usually get my car repaired, the guy there who I trust completely told me to fill the car right up with petrol which would apparently water down the diesel, the car took 29 litres of unleaded petrol before it was full. I then did a 22 mile drive on the dual carriageway at an average speed of 70mph. The car is still smoking but nowhere near as much and it seams to be running ok. I hope I haven't done any damage to the engine?

I'm convinced I didn't fill up with diesel and never have in all the years I've owned Volvo 340's, in fact I returned to the garage with my receipt to see if there had been a problem with pump 8 being mis-filled but the very arsey lady behind the till said that would be impossible!

weird dude.
at least its running through alright.

im gonna start checking my reciepts before i restart the car!

Keep topping it up with U/L and eventually Satan's fuel will be banished and all will be well.

Heavy oil-keep it in your wagons please.

Might be a handy way to check your mpg while you're on.

Petrols take a drop of derv better than vice versa-luckily for you.

ive always been told a bit of diesel in petrol helps clear injectors and a little bit of petrol in the old diesel helps clean pipes or some lark.

Im still yet to mix fuel. quite happy to mix normal diesel with red though...

Keep topping the thing up with unleaded, everytime you think you can get a fiver in do so. As Sven says, that way round isn't horrendous.

If you do it the other way round, i.e. unleaded in diesel, chuck in 2 stroke oil, as well as topping up with diesel, it'll keep the fuel pump lubed

it wouldnt take a lot for somene to put the wrong nozzle in the wrong slot!i.e you look at the slot(reads unleaded)then grab that pump not realising it actually belongs in another slot marked (diesel)almost did it in my dads scoobie once!

My '80 343 runs on 98 RON super unleaded, and here Shell has recently started selling "V-Power Diesel" as well as "V Power". Easy to grab the wrong pump ...

Tom

Im still driving on the 8 litres Diesel/29litres Unleaded mix and did a 130 mile round trip yesterday (Friday), the car ran pretty well although it was a pig to start.

Today (Saturday) my fuel gauge is reading about half a tank and its running like a pig, loads of smoke, a couple of backfires and the accelaration is a lot slower than normal, as if somethings holding the car back.

I have a terrible feeling I've damaged the engine with the accidental diesel/fuel mix?

I just pray that when I finally need to fill up again that when there's petrol in there it will run a lot smoother.

J

I'm always really paranoid about this and check the pump, and the bit in my hand twice before starting to fill

I'm sure I'd get confused if I started driving a diesel

dont wait for it to be empty! keep topping it up as often as you can. it should be fine as long as you keep putting petrol in it! my mate done this once, it was worrying but it soon cleared up 2 or 3 tanks of fuel later!

Justin wrote:Im still driving on the 8 litres Diesel/29litres Unleaded mix and did a 130 mile round trip yesterday (Friday), the car ran pretty well although it was a pig to start.

Today (Saturday) my fuel gauge is reading about half a tank and its running like a pig, loads of smoke, a couple of backfires and the accelaration is a lot slower than normal, as if somethings holding the car back.

I have a terrible feeling I've damaged the engine with the accidental diesel/fuel mix?

I just pray that when I finally need to fill up again that when there's petrol in there it will run a lot smoother.

J

This might be because Diesel is heavier than petrol and after sitting overnight the diesel sank to the bottom - therefore the fuel mixture at the start would be more diesel again. Don't worry about your engine, the most you'll have to do after this is replace the spark plugs, fuel filter and possibly bleed the fuel lines. I doubt even that though.

As has been said several times before you need to lean that $hit out of there ASAP.
Every time the tank drops more than a fiver,brim it 'til finally that Godforesaken junk is out for good.

As an aside have you noticed if you get more mpg on diesel as I have heard that's one of the advantages of DERV??

MJ wrote:I'm always really paranoid about this and check the pump, and the bit in my hand twice before starting to fill

I'm sure I'd get confused if I started driving a diesel

Checking is good, specially with several cars, two diesels and two petrols, also one has filler cap on different side than others, there is always bit of memory test when going to pump station. Of course it helps a bit as Volvos are not road worthy at the moment.

The smoking once its sat will be because the Diesel, being a heavier fraction of oil will sit down in the bottom of the tank and get sucked up first. You'll get away with it, but someone I know managed to blow his car up having tried to do the same thing.

He put half about 10 litres of diesel in before he noticed, and then brimmed it up with petrol. Unfortunately after it sat for a few days, it was smoking like anything, and he was sat there revving it blowing smoke all down the road. When I next spoke to him a few weeks later the car was toast......I think either the exhaust got very hot and set the grass underneath the car on fire, or there was a massive backfire or summat and the whole thing started burning. Anyway, the fire brigade had to be called out.

If its smoking too bad and not running right, then the best thing to do is empty the tank tbh. Luckily there's no cat otherwise that will get damaged by all the diesel fumes too. If you can manage to keep topping it up with petrol and it keeps going then fine, but if you get to a point where all the diesel sinks to the bottom and it won't start one day then you're best off draining the tank out. If not all the way then at least the bottom part where most of the diesel has gathered. Best way is a siphon through the sending unit in the boot. Fill a fairly long hose with some petrol and keep your finger over the end. Then carefully dunk it into the petrol tank, once the fuel starts flowing stick it right into the bottom so it gets the heavy diesel out. Get out a couple of gallons from the bottom will have got rid of most of it. Then brim the tank again. Keep the waste diesel/petrol and dilute it down 50:50 with petrol you should be able to use it in your lawnmower or chainsaw etc.

My brother is alway's running his 140 on petrol derv mix. It's never done the engine any harm but if there is a fair bit of derv in the mix it does go a bit lumpy. I'm sure the old b20 would run on piss after a heavy night on the pop!

Your 300 should be fine but keep topping up with petrol and rock teh car about to mix the fuel.