Grandson rang to excitedly tell me he'd bought a new car. It's a '06 Mondeo 2.0 Tdci with 100.000 K. He's bought from a dealer who is well known in the area and reputable over many years of trading.

 

Whist telling me all about it he said the dealer had told him it had petrol put in by mistake but assured him it had been 'worked on in his garage and was now fine with no damage'.

 

I asked him how far the car was driven and how much petrol was put in and was it on an empty tank etc but he hadn't asked these questions.

He has paid a deposit and is to collect next week.

 

I have told him he needs to find out much more about the incident and if it were me I'd be getting my deposit back and looking elsewhere.

 

Can anyone say if they have experienced this and could the car still be okay?

 

He's paying £1000 for the car.

Edited 21 November, 201411 yr by horkin

petrol in diesel in my opinion is fine. I guess it depends how much petrol, but in older diesels people used to put petrol in over winter regularly.

 

There will be techies who say ooh no the car is dead, but I think thats just a garage line. I know a couple of people who run old diesels on misfuel.

If I'd done it myself to my own car I might have given it some thought.

 

But if I'd not yet bought the car I'd have to consider walking away.

 

It's not like there is a shortage of used cars

Edited 21 November, 201411 yr by Aspman

petrol in diesel in my opinion is fine. I guess it depends how much petrol, but in older diesels people used to put petrol in over winter regularly.

 

There will be techies who say ooh no the car is dead, but I think thats just a garage line. I know a couple of people who run old diesels on misfuel.

 

Interesting view and if you're right it certainly would help me to stop worrying . 

 

I just thought petrol is a 'cleaner' and would strip the lubrication that diesel offers and that diesels are designed to operate on resulting in damage.

 

Bloke at the garage seems confident and has offered a 3 months warranty. 

 

It would be nice to know though if the previous owner realised what he'd done and either not started the car or driven only a short distance. I've asked him to go back and try to find out.

 

Thing is, looking on auto trader a car in nice condition with this year and mileage sells for £1500 to £2000 so he's getting it cheap enough if it's okay.

Edited 21 November, 201411 yr by horkin

Not  a bad price, just get him to check the Injectors as on the Mondeos they are a weak spot on the engine and cost about £700 to replace.

Petrol is a cleaner, but whats it going to remove lubrication from? as soon as diesel runs through the system again its all lubed up again.

 

How different are diesels to petrols anyway, apart from the obvious spark plugs etc

It's happened to me 3 times, once by myself in my own car, and twice in showroom cars at the dealers I used to work at by the apprentice sent to fuel them.

 

As soon as the petrol runs through - about 100 yds max - the engine simply stops.

 

It's a damn nuisance, but far from terminal. In my personal case, once recovered, drained and refilled & primed the car ran fine for another 25,000 miles without a hitch.

petrol in a diesel is fine, the other way round is not though.

 

proper cold countries add petrol to diesel to stop it freezing

Not a bad price, just get him to check the Injectors as on the Mondeos they are a weak spot on the engine and cost about £700 to replace.

+1. My S-Max had an injector replaced less than 3 months after I got it. I'd strongly suggest that he walks away or puts a decent warranty on it.

Petrol is a cleaner, but whats it going to remove lubrication from? as soon as diesel runs through the system again its all lubed up again.

How different are diesels to petrols anyway, apart from the obvious spark plugs etc

I was always told that diesel in a petrol engine isn't a major problem, it'll just choke the spark plugs, something I have had first hand experience with when a bloke at work filled the petrol jerry cans with diesel: lead to flushing two ride on mowers , a quad bike and two pedestrian mowers, but no real harm done. However petrol in a diesel, can definitely, I am told, cause problems. Especially in the modern common rail engines (I would assume the car in question is a common rail system). If the driver does not realise they've mistakenly put petrol into the tank and drives the car for long enough that the petrol starts to circulate into the engine, it, as you said, 'cleans' the lubricating properties that have been left there by the oils in the diesel, leaving metal to metal contacts in the engine. Metal to metal under thousands of psi of pressure with no lubrication except the slight amount given by the viscosity of the petrol. Not really what an engine is designed to withstand, not for any prolonged period of time anyhow.

I am no mechanic however and this is all second hand information (granted from a BMW mechanic). And there will no doubt be diesel engines that have been driven on numerous occasions with the wrong fuel and don't seem to have suffered much in the way of a detrimental effect.

On the flip side of the coin I am told the engine used in the car in hand is a really good workhorse and has been known to do three times the mileage the one in question is on with no real problems.

A friend has the same car and filled the tank with petrol, drove down the road until it began to splutter, pulled over and realised what he had done, the engine and tank was emptied and flushed, and replaced with diesel and with the exception of a few 'coughs and splutters' for the next fifty mile or so, the car ran fine. It has done twenty of so thousand miles since the incident with no sign of any fault.

The mine field of buying second hand cars I suppose.

Fingers crossed the car has received the care and work necessary and doesn't give your lad any problems.

JRJG

Diesel TDCI (commonrail) engines run a fuel rail pressure of over 1000bar, way higher than petrol engines get to. Petrol going through the system at such high pressures means that apart from stripping the lubrication from the fuel lines, it also strips the lubrication at high pressure from the seals in the solenoid valves etc. in the [not really very cheap] injectors, and also in the high pressure fuel pump. If it were my buying the car I'd be asking for 2 years warranty on the affected parts (fuel pump, injectors, etc.) and have it in writing.

If the fuel pump gets destroyed for any reason, it will invariably take all four injectors with it. That adds up to a hell of a bill which I wouldn't want to be paying if it were me.

The dealers have sort of committed themselves to being responsible by admitting that it's been mis fueled, so I would stick them for a warranty on the parts and don't budge.

 

Edit: Having just forked out for a refurb on a set of 4 TDCI injectors which cost me £550 all in, on a vehicle which hadn't been mis fueled, I should think that petrol damage won't help on another vehicle really.

I had a (works) mondeo estate 2.0tdci and misfuelled it twice in one month, over the course of about 2 years working at the company (approx 50k miles a year) it only ever let me down due to an EGR fault.  Never a problem from the misfuel and on both occasions I left the petrol station and only knew what I had done when it choked out on the motorway.

 

Apart from embarassment and annoyance no consequence from the petrol going in.

 

That said if the risk of issue/complication is low, the garage is not taking on any great risk by writing you a warranty.  If they baulk at giving the warranty then i would argue with them that this is an admission that the car comes with elevated risk of producing an expensive fault.

 

Try throwing that at them and see what they say.

Diesel TDCI (commonrail) engines run a fuel rail pressure of over 1000bar, way higher than petrol engines get to. Petrol going through the system at such high pressures means that apart from stripping the lubrication from the fuel lines, it also strips the lubrication at high pressure from the seals in the solenoid valves etc.

^ That is a better description of what I had been told.

1000 bar is around 14'000 psi isn't it!? I didn't realise it was as high as that, good grief.

JRJG

Well, had a word with him this morning and he's decided to go with it. I've told him the risks but as he says, the guy is straight enough and after all he (the dealer) didn't really have to mention the mis fuel.

 

Grandson has taken out a 2 year extended warranty with 'Autoguard'?. He's come to an agreement that if there is a fault that they don't cover, the garage will 'help him out with it'.

 

Just to mention Grandson has a clapped out Corsa 1.0 with 120K on the clock and the dealer has given him £350  so he's only parting with £700 cash which I thought was not a bad deal and he doesn't stand to lose a lot (so long as the Mondeo is good for a while that is).

 

As for the mis fuel. My concerns are as stated by some, there may have been a period of lack of diesel lube on the pump and at the injectors, but it goes back to how much pure petrol went through and how long the engine was run and those are the factors I don't have.

each time I did it my car made it about 3 miles (ish) before it conked out.

1000 bar is around 14'000 psi isn't it!? I didn't realise it was as high as that, good grief.

JRJG

 

Indeed it is. Only about half the pressure generated by the PD injectors in the VAG range.

My boss put a full tank of petrol in his diesel jaguar (new at the time - around 2010)

Bill for whatever it busted was 3 grand

My boss put a full tank of petrol in his diesel jaguar (new at the time - around 2010)

Bill for whatever it busted was 3 grand

 

Frightening!! sounds like he had the engine replaced.

My boss put a full tank of petrol in his diesel jaguar (new at the time - around 2010)

Bill for whatever it busted was 3 grand

I was told a story by a bloke who bought a brand new Mercedes 'GL' (one of the bmw x5/ range rover size ones).

A few days after picking it up from the dealer it started to make an awful 'grinding noise'

He took it back and they asked him to drive in a bay next to one of the garage doors so that it could be taken inside and put onto ramps, as he got towards the door a mechanic ran out waving his arms shouting 'turn it off!'.

...

The car had no oil in it!

Why the oil light hadn't come on was never discovered. But what was discovered was the need for an entire new rebuild.

JRJG

Petrol in a modern Diesel can cause issues with all the seals in the system.

I would be more worried about the injectors though as they are a problem on fords.

If he has decided to go ahead the he should insist that the fuel filter is replaced if it has not already been done.

My dad put petrol in his 56 reg Jetta once, car drove about 7 miles, and simply stopped. Car got picked up and taken to a garage, petrol drained out diesel put in, key turned and it started straight away, never needed a spanner since. And that will be about 4 years ago now.

Yeah I put petrol in my Fabia vRS a few years back, as above it just started and ran after new filter and diesel. It's a PD though, so bit different to the CR motor in the mondeo. My dad had one and spent £2000 trying to get his to run right, injectors, turbo, DMF etc so check it over properly. 

I saw a misfuelled Diesel Jaguar XF the other week, it needed a new high pressure pump, injectors, fuel lines, filter and the tank removed for cleaning.  The bill was around £4500.  Petrol in a modern diesel can cause a lot of damage, whereas diesel in a petrol isn't much to worry about.

each time I did it my car made it about 3 miles (ish) before it conked out.

 

each time!?

 

You do realise the definition of insanity is "doing the same thing over and over again and expecting different results" :think:

Worst ive seen is years ago out in Germany.

Chap left a 1 month Old Toyota Supra with his good lady whilst he went away..... Showing basic fluid checks and washer top ups..

Unfortunately, she topped up the washer fluid in the wrong cap.... The oil filler cap.... Right to the top...

Trying to start the car until the battery went flat caused rather a lot of issues.... Bless