Engine: D52447: Petrol in a diesel car – misfueling.

[d3cym]

Had 1/4 tank of diesel in my British gas transit and put 12L of unleaded in it by mistake and filled the rest with diesel, it ran like a bag of **** until I used the full tank and after that it was a flying machine, was the oldest van on the patch too lol.

[Yogi2010]

After 2 years of ownership of my XC90, last Friday I mistakenly put 30 litres of unleaded in my 2.4 D5. I didn`t even realise I had done it. My mind was obviously elsewhere after a very demanding week at work. I had 1/4 tank of diesel before I added the extra 30 litres. I use my XC to tow our caravan and we were going away on Friday evening. It was during our journey that evening (whilst towing the van) that the car began to splutter with a lack of power. I still didn`t realise what I had done and the XC drove us 60 miles to the campsite! It was only when we got there and I checked the fuel receipt that I realised my mistake.

So, I`ve managed to drain the fuel tank through the fuel filter housing by switching on the ignition and activating the fuel pump. I`ve drained 25 litres out so far. The fuel gauge has dropped from 3/4 to 1/4 but I can`t pump any more out? I`ve fed 2 metres of syphon pipe down the filler neck and can`t get any more out this way, in fact the pipe comes out dry? Having read the many other posts above I can only assume I still have 1/4 tank of fuel in the 2nd half of the tank. How do I get at it to drain it out? or is my fuel gauge reading incorrectly (never had a problem before with it though).

Anyone else experienced this?
Nick

[Clan]

Originally Posted by Yogi2010

After 2 years of ownership of my XC90, last Friday I mistakenly put 30 litres of unleaded in my 2.4 D5. I didn`t even realise I had done it. My mind was obviously elsewhere after a very demanding week at work. I had 1/4 tank of diesel before I added the extra 30 litres. I use my XC to tow our caravan and we were going away on Friday evening. It was during our journey that evening (whilst towing the van) that the car began to splutter with a lack of power. I still didn`t realise what I had done and the XC drove us 60 miles to the campsite! It was only when we got there and I checked the fuel receipt that I realised my mistake.

So, I`ve managed to drain the fuel tank through the fuel filter housing by switching on the ignition and activating the fuel pump. I`ve drained 25 litres out so far. The fuel gauge has dropped from 3/4 to 1/4 but I can`t pump any more out? I`ve fed 2 metres of syphon pipe down the filler neck and can`t get any more out this way, in fact the pipe comes out dry? Having read the many other posts above I can only assume I still have 1/4 tank of fuel in the 2nd half of the tank. How do I get at it to drain it out? or is my fuel gauge reading incorrectly (never had a problem before with it though).

Anyone else experienced this?
Nick

you need to put the pipes back together as normal and carry on activating the pump , it will take a while but it will transfer the fuel from the left side to the right side where the active fuel pump is . You can then continue to do what you were doing before with the fuel filter pipes , ign on for a minute and off and on again etc ..and drain the right side ... . you might have to do this a few times ...

[Tannaton]

You don't need to get every last drop out - a modest amount of petrol in the diesel wont make too much difference. Sounds like you've been running an about a 33/77 diesel/petrol mix anyway!

The car will probably be fine afterwards, you might even think it runs better.

[Yogi2010]

Clan - I didn`t disconnect any pipes. All I did was to undo the bleed screw on the fuel filter and then turned ignition on and off countless times to squirt the fuel out into a container. I`ve reached the point where I just get a gurgling sound like it`s virtually empty but the fuel gauge shows 1/4 tank?

[Biodieselgrandad]

I put petrol in my biodiesel in winter to thin it and stop it waxing.
Anything up to 20% makes no difference to the running.

[Tannaton]

Originally Posted by Biodieselgrandad

I put petrol in my biodiesel in winter to thin it and stop it waxing.
Anything up to 20% makes no difference to the running.

I agree, a small mix of petrol makes little difference and in some cases I think is beneficial for cleaning properties. Any forecourt attendant will tell you that drivers of all sorts of (usually older) diesel vehicles will occasionally top up with unleaded.

However you do have to be a little careful as some manufacturers fit sacrificial fuel quality sensors which will stop the engine/put into restricted power if petrol is detected (e.g. Jaguar). Not sure how much petrol needs to be there to activate it.

[Yogi2010]

Decided to investigate further tonight as to why the fuel gauge still showed just over 1/4 tank. I removed the 2nd row of seats and carpets and located the fuel level sender on the passenger side. As I understand it this sender unit measures the lower fuel level. I made up a tool to undo the knurled ring that holds the sender in place. As I began to undo the ring, Diesel began seeping from around the sender unit. This confirmed my suspicions that the passenger side fuel tank still had fuel in it.
Why has the drivers side fuel tank emptied only? I thought the 2 tanks were linked via a hose that runs from the higher sender unit across to the passenger side tank to keep the fuel levels in both tanks balanced? The pump no longer pumps any fuel out. Strange.
Hopefully I will be able to syphon the remaining diesel out through the sender unit hole once I get it out.

[Clan]

Originally Posted by Yogi2010

Decided to investigate further tonight as to why the fuel gauge still showed just over 1/4 tank. I removed the 2nd row of seats and carpets and located the fuel level sender on the passenger side. As I understand it this sender unit measures the lower fuel level. I made up a tool to undo the knurled ring that holds the sender in place. As I began to undo the ring, Diesel began seeping from around the sender unit. This confirmed my suspicions that the passenger side fuel tank still had fuel in it.
Why has the drivers side fuel tank emptied only? I thought the 2 tanks were linked via a hose that runs from the higher sender unit across to the passenger side tank to keep the fuel levels in both tanks balanced? The pump no longer pumps any fuel out. Strange.
Hopefully I will be able to syphon the remaining diesel out through the sender unit hole once I get it out.

there is a venturi device in the left tank which needs the return line to draw the fuel into it and transfer it to the swirl pot on the right side so if you are draining from the filter there is no return flow therefore the left side will stay full .
You need to put the fuel filter back to standard ( shut the drain **** ) and then carry on running the pump , it will then drag the fuel from left to right , it will take a time though . Then you can continue draining as you were until it runs dry again , then repeat the process until the gauge is down in reserve , should be safe to fill up with diesel then .