VW Passat - Anyone advise please?

FrenchieBoy

Well-Known Member
I have one of the older VW Passat Deisel Estates and have done the most stupid thing! I called in to a garage that I don't usually use and got £10 worth of deisel - Or at least i thought I was putting diesel in.
The car drove well enough for about 8 miles till I got to a friends place but then the engine "died" just as I was paking up and would not start again. After looking around what had happened dawned on me. I took the fuel filler cap off and could smell petrol.
There was no knocking from the engine and it drove well enough between the garage and my mates place so I am sure that I haven't damaged the engine. I can't do anything about it till Friday as I am in hospital tomorrow (Only for my annual heart review, and I don't think there are any problems in that department) and then I am away on a day trip with the elderly from our flats on Thursday.
I have another good friend who lives just round the corner from where the car is broken down and on Friday we are going to tow the car to his lock up garage and drain the system, pit a new fuel filter onit and then get it going again with fresh DIESEL!
What I need to know in advance is: Is there a fuel drain plug on the tank or will we have to drop the tank to drain it out.
Can anyone advise please?
 
I have one of the older VW Passat Deisel Estates and have done the most stupid thing! I called in to a garage that I don't usually use and got £10 worth of deisel - Or at least i thought I was putting diesel in.
The car drove well enough for about 8 miles till I got to a friends place but then the engine "died" just as I was paking up and would not start again. After looking around what had happened dawned on me. I took the fuel filler cap off and could smell petrol.
There was no knocking from the engine and it drove well enough between the garage and my mates place so I am sure that I haven't damaged the engine. I can't do anything about it till Friday as I am in hospital tomorrow (Only for my annual heart review, and I don't think there are any problems in that department) and then I am away on a day trip with the elderly from our flats on Thursday.
I have another good friend who lives just round the corner from where the car is broken down and on Friday we are going to tow the car to his lock up garage and drain the system, pit a new fuel filter onit and then get it going again with fresh DIESEL!
What I need to know in advance is: Is there a fuel drain plug on the tank or will we have to drop the tank to drain it out.
Can anyone advise please?


Well, the good news is that
1. You only put in £10s worth
2. You have a mate that can help

I put £80 in an S-Max, spent £120 getting it drained, and then a further £80 filling it back up!

They tipped the car a bit, then put a pump into the tank via the filler cap to drain it. As I'd only driven about 50' there was no damage to the engine/filters etc..., so can't comment on what remedial work you'll need, but as this happens all the time, I'll bet that a quick Google will pop up some thoughts.

Good luck
i.
 
I'd doubt there's a drain on the tank , and you'll have a huge job to take the tank out aswell

id suggest a call to the AA or who ever your with and they'll Suck it out it'll be less hassle
 
Take the fuel line of in the engine compartment, attach a further bit of pip to reach the floor or into a ground level container,

Switch on the egnition and let the fuel pump run until the tank is empty,

When empty, fill with a small amount of diesel ...3 ltrs ish, do the same as above,(flushing out the petrol and crud)

Fill with some clean fuel and then run the pump until it shows at the engine block end.(bleeding it)

When this is done swith off egnition reconnect the fuel line to the injector block and start the engine,

Bob,


Make sure you have a good battery as this can drain a winter shy one in no time.
 
Last edited:
If it's only a tenners worth change the filter put 50 notes worth of derv in the tank bleed it up and drive. I wouldn't worry about it! In some cases the petrol can affect the seals in the fuel pump also petrol doesn't have the lubricant property's of derv but this will not be apparent until you got it running
 
Think the AA take the filter off and attach their pump to the inlet pipe. One of those pumps that fit onto a drill might do the job.
 
How old?
diesel pumps require diesel to lubricate them unfortunately

DO NOT PUMP THAT STUFF THROUGH THE DI PUMP TO DRAIN, not good advice
the engine will run fine on petrol, or veg oil or coal dust

the delicate bit is the direct injection pump if you have one


I was was going to describe how to get the pump under the rear seat to pump the tank empty but suspect you have a secondary pump on the block depending on the age and model

diesel pumps need to be primed also, you can't just crack the seal and then reconnect

how much was in the tank when you filled it?
 
Last edited:
How old?
diesel pumps require diesel to lubricate them unfortunately

DO NOT PUMP THAT STUFF THROUGH THE DI PUMP TO DRAIN, not good advice
the engine will run fine on petrol, or veg oil or coal dust

the delicate bit is the direct injection pump if you have one


I was was going to describe how to get the pump under the rear seat to pump the tank empty but suspect you have a secondary pump on the block depending on the age and model

diesel pumps need to be primed also, you can't just crack the seal and then reconnect

how much was in the tank when you filled it?

There was only a gallon or so (Maybe a little less) in the tank when I pulled into the garage so there will be about 2.5 gallons to drain.
I am hoping that by disconnecting the inlet pipe that goes to the fuel filter and then connecting a syphon to it we will be able to drain the tank. If we can drain the tank that way we will then put a good few gallons of fresh diesel into the tank and then take the old fuel filter off and replace it with a new one after filling it with fresh diesel, then bleed the system at the injector pump.

Hopefully that will work, any thoughts?
 
Suck the contaminated fuel out then sprinkle lightly over the soft interior then WHOOSH!
 
It's not a Landrover so that not required :). Dependant upon age it may just require rear uplift pump, As Bewsher500 pointed out further info required.


the fact it stopped running may have a BEARING on the problem.

a much much older one will run on whatever you feed it:evil:

Suck the contaminated fuel out then sprinkle lightly over the soft interior then WHOOSH!
 
not sure on your car but on most of the cars I have had there is a way into the tank under the rear seat. when I did the same as you but with a full tank I unscrewed the lid under the seat, removed the lift pump and pumped out with a small air pump until empty. filled with diesel and job done.

good luck!
 
Fill it with diesel , empty the filter and wind it over till it starts, put 3/4 tank of petrol in a ranger, just kept topping it up, over 70,000 miles later still running, we used to put petrol in with the diesel in severe cold weather to stop it waxing in the tractors, putting diesel in a petrol engine now that's a bitch if you start it up.
 
Fill it with diesel , empty the filter and wind it over till it starts, put 3/4 tank of petrol in a ranger, just kept topping it up, over 70,000 miles later still running, we used to put petrol in with the diesel in severe cold weather to stop it waxing in the tractors, putting diesel in a petrol engine now that's a bitch if you start it up.
Correct Taff if the injection pump is an "in line" and not a rotary type. Rotary pumps have much tighter settings and will sieze and break the main shaft and bearings if a pollutant is fed into it whereas a rotary will pump just about anything.
Two gallons of petrol topped up with diesel would do no harm i think.
I had a VW Caddy that got a mug full of power washer soap into the system and it needed the tank removed and a new rotary pump and filter but luckily the injectors were fine. If this car is turning over and not firing at all the injector pump is sheared inside due to a woodruff key on the internal shaft breaking off. If it is trying to start fill it up to the top with diesel and give the car a good shake to mix the fuel and it will be fine at a 5/1 diesel to petrol mix.
 
Best way I have seen to clean diesel out of a petrol engine was to take the air filter off, take the ether starter off the tractor and spray direct into carb as your mate turns it over, one word of advice though, don,t stand too close to avoid hair loss, also your rev counter may get stuck in the red.
 
Two gallons of petrol topped up with diesel would do no harm i think.

it stopped running!
that is harm

fuel delivery issue likely down due to pump failure/seizure (not a fuel issue as they will run on petrol, it's a fuel delivery issue)
can be repaired but if you try running it further with more lighter cleaning agent (petrol) you risk shagging it completely and as it is not firing running a 60% mix of petrol into the bores and washing the bores out, filling the sump with 60% petrol, mixing the engine oil and cranking the engine bearing on a nice clean shell....


mmmm...your call, but diesels need oil more than petrols
 
Thanks for all the advice guys. I believe that it has an electrical rotary pump which is situated inside the tank and is accessible from under the rear seat.
Our plan for Friday is to remove the pump/sender unit from the tank and then drain everything from the tank - The pump should steadily drain much of the petrol infested fuel out of itself as it is removed. We will then need to remove the fuel filter and blow the feed pipe through from the tank end to empty the feed pipe. Next we will disconect the return pipe from the filter housing and blow the contaminated fuel out of the injector pump with an air line through the feed pipe after disconnecting it from the fuel filter housing. Before fitting a new fuel filter we will put some fresh diesel into the tank, refit the fuel pump/sender unit and then switch the ignition on, this should pump fresh fuel through to the filter housing and tell us if the pump is damaged and needs replacing or if all is well with the rotary pump. Assuming that all is well, with the outlet pipe from the fuel filter and the return pipe on the filter mounting we should (Hopefully) be able to blow the contaminated fuel out of the injector pump. We will then fit a new fuel filter and reconnect all the pipes and then it should be just a matter of bleeding the system through and hopefully be able to get the engine running again.

I have to get ready to go for a hospital appointment now but will check this thread again tonight in case anyone has any suggestions or sees any pitfalls in the way we plan on going about things.
Once again, thanks for all the advice guys, it's apreciated!
 
Hi phone Fuel Doctor 03334449000 / 08454590000. It`ll cost around £130. The guy Paul Sutherland comes to your house within the hour. Paul I know personally and he won`t rip you off. You could get away with a small amount of petrol in diesel years ago as previously stated but not to be recommended now.

Hope you get it sorted out.

The Spaniel.
 
Hi phone Fuel Doctor 03334449000 / 08454590000. It`ll cost around £130. The guy Paul Sutherland comes to your house within the hour. Paul I know personally and he won`t rip you off. You could get away with a small amount of petrol in diesel years ago as previously stated but not to be recommended now.

Hope you get it sorted out.

The Spaniel.

Thanks for that mate. I'll bare that in mind if we do come across any problems.
 
I have not had a Diesel car in a while ( Mercedes, Peugeot, BMW ) but they all had a sump ( low spot in the fuel tank) to catch water condensate, and a drain plug to let it out. The fuel lines used to all have a water separator, too, where you could drain all that fuel away. Diesel cars, trucks, and tractors are just made to be drained, for several reasons, one being that the formulation changes with the seasons, and old fuel does go bad.

You can always siphon it out through the filler spout with a squeeze bulb in the line to start it, but that will not get all the gasoline.
 
Back
Top