Petrol in a Diesel

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Petrol in a Diesel

Post by MULTIMENTAL »

Just bought a 406 2.0 hdi. Full service history, money spent on it whenever needed, lovely. Just been going through the wealth of history that I got with it and noticed that it's had 1100 quid spent sorting it out after petrol was put in it. Now, it runs great and doesn't appear to be any the worse for wear from this.

My question is, will this cause me probems in the future?
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Re: Petrol in a Diesel

Post by myglaren »

Unlikely.
My daughter bought a C3 1.4 HDi a few years ago and the dealer (Honda) filled it with petrol before handing it over.
It conked out halfway home (6 miles) was recovered by the dealer and sent to Citroen (across the road) for repair.
That also cost about £900. Tank drained, fuel system flushed, filters replaced, pumps stripped and cleaned etc.
Work was warranted for a year.

Never another problem with it in the three years she kept it.
Part exed for a Mini Cooper (original mini) that never went a week without a problem.
She has another C3 now :)
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Re: Petrol in a Diesel

Post by MULTIMENTAL »

Thanks Steve, that's put my mind at rest.
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Re: Petrol in a Diesel

Post by Peter.N. »

I would agree, they will run on a mixture of petrol and diesel the main problem being the lack of lubrication from the petrol, if its been running OK since it happened it should be fine.

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Re: Petrol in a Diesel

Post by spider »

I know the older units are a bit more durable to survive this provided there is enough derv for lubrication still present.

I wonder if the high pressure of the direct injection units compared to indirect has any bearing (no pun intended) on the potential damage. ie petrol at that kind of pressure...
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Re: Petrol in a Diesel

Post by Peter.N. »

I know from experience that the pumps can be very sensitive to changes in viscosity, especially when worn. My C5 became increasingly difficult to start as the pump wore but almost impossible when hot due to the fuel being thinner, so I wouldn't think they would pump neat petrol very well, in fact it maybe lack of rail pressure that stops them when fuelled with neat petrol I'm sure you are right Andy, at about four times the pressure of an IDI engine the lubrication is even more important.

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Re: Petrol in a Diesel

Post by wheeler »

myglaren wrote:Unlikely.
My daughter bought a C3 1.4 HDi a few years ago and the dealer (Honda) filled it with petrol before handing it over.
It conked out halfway home (6 miles) was recovered by the dealer and sent to Citroen (across the road) for repair.
That also cost about £900. Tank drained, fuel system flushed, filters replaced, pumps stripped and cleaned etc.
Work was warranted for a year.
I would have refused the car unless all the fuel pump(s), injectors & filter was replaced plus the tank & lines thoroughly flushed through. That would have been more than £900 in parts alone. Pumps 'stripped & cleaned' ? I'm afraid cleaning won't really do anything as any damage would already have been done as they have been run with insufficient lubrication. Although there never appeared to be any issues you just never know if the injectors or pump that would normally have lasted 150k miles would only last 100k miles etc.
Most manufacturers now when a car is mis fuelled when the car is still under warranty say pretty much the full fuel system has to be replaced (which could easily be an insurance job), if you say no & just opt for a drain & refill they put the car on a restricted warranty register meaning they can wash their hands of pretty much any running problems in the future.
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Re: Petrol in a Diesel

Post by Northern_Mike »

I remember seeing an article some time ago from a somewhere, with a reputable source that referred to the "great misfuelling rip off", in which various people who should know picked apart the theory that misfuelling knackered engines and pumps, and the whole thing is a myth / a dealer con to get you to cough up lots of wedge for unnecessary repairs..

I shall root it out and post it !
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Re: Petrol in a Diesel

Post by Peter.N. »

Please do. I think as with most things that the truth lies somewhere in the middle.

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Re: Petrol in a Diesel

Post by spider »

The few early HDi pumps (going back to when the 2.0HDi was brand new around 99) that broke up and sent metal around the fuel system, it was about £3K to rectify as everything fuel related was replaced more or less.
Andy.

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Re: Petrol in a Diesel

Post by wheeler »

Northern_Mike wrote:I remember seeing an article some time ago from a somewhere, with a reputable source that referred to the "great misfuelling rip off", in which various people who should know picked apart the theory that misfuelling knackered engines and pumps, and the whole thing is a myth / a dealer con to get you to cough up lots of wedge for unnecessary repairs..
That may be true & if I mis fuelled the car myself I would just drain it & re fill + new filter, if anything goes wrong with it in the future then it's my fault. if a garage done it then then I would insist everything was replaced as it may not show any issues straight away & I would be very unhappy if the pump/injectors failed prematurely a few years down the line. Also if I manufactured fuel components & I found the engine had the wrong fuel(therefore insufficient lubrication) going through them then I would not warrant the components.
HDi fuel components are manufactured to very fine tolerance's, The Siemens piezo injectors for example only open by 0.04mm to deliver fuel. Running these poorly lubricated surely has to have some sort of effect on them ?
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Re: Petrol in a Diesel

Post by spider »

I used to wonder why the filler necks were not changed along with the pumps. As you know you cannot physically get a derv nozzle into a petrol car (well not a newish one anyway) as the old leaded 4star used to have the larger nozzle and then manufacturers / fuel retailers made the unleaded one smaller to stop people killing their catalysts with leaded fuel.

Problem here is:

diesel in a petrol car (assuming you manage to get it into the tank!) = a lot of smoke then it will eventually stop, probably without any serious damage maybe want plugs cleaning and a cat if you're unlucky.

petrol in a diesel car (newish one) nasty running and a large bill for a pump and injectors if you're unlucky as indicated the tolerances (and pressures!) on the DI units are a lot higher than IDI. The older IDI ones used to leap around badly when someone put petrol in them.

Cannot see an easy solution, I think the designers (including fuel retailers and car manufacturers) perhaps did not look ahead enough. The change of nozzles seems back then early 90's to be designed to protect catalysts which is OK but they must of known leaded fuel was going to be phased out so there was little point.*

* Apparently its not "banned" you can still obtain * proper petrol :D * from certain limited outlets at a sky high price.

EDIT... I think the summary here is older engine designs both say carb petrol and indirect injection diesel are a lot more tolerant of a petroderv or dervpetro "mixture" , I've seen a monopoint 106 run terribly with some 'mixed' fuel although I think if it had been carb it may of ran better.
Andy.

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Re: Petrol in a Diesel

Post by JohnD »

A couple of weeks ago I took my C5 and caravan down to the New Forest area. I set off with a fairly full tank and the drive down was fine with the car performing correctly. A few hours after arrival I went out to do some shopping at a local Tesco superstore. As I passed the filling station on the way out I decided to top up the tank. I filled until the pump clicked off and went to pay the £26. I set off back to my site - about 6 miles away - no problems. Next day I drove about 15 miles and unloaded my bike. After riding a bit I returned to the car. The engine didn't run very well so I stopped and switched off. After restarting, all was back to normal, but then I started getting beeps and messages. Depolution system faulty; ESP system faulty; Speed control system faulty; and the service light. Running was as normal. When I got back to site, I disconnected the battery for 20 minutes. After a restart, everything back to normal - for about 10 miles - then the messages came up again. Fortunately at the end of the lane to the site, there was a Citroen/Peugeot Indi. I went in and described the symptoms. He connected his Lexia. The only odd thing he could find was the fuel pressure extremely high. He removed the fault code, charged me £20 for the diag and told me to return if the faults reappeared. They did after about 10 miles so I returned. I left the car with him and he phoned me 3 hours later to tell me that he thought there was petrol in the fuel and it would have to be drained and filter changed. I told him to go ahead. I collected the car in the evening, just as they were refixing the tank. They put diesel in, connected the Lexia and went for a drive. Job done and all running perfect. For 10quids worth of diesel, new filter and VAT, I paid £275. I talked to the guy about the fuel mix. His opinion was that there wasn't much petrol in it, in spite of the tank being almost full. I returned to Tesco, told them which pump I'd used and asked if they had other complaints. Apparently they hadn't. Only conclusion I can come to is that I did indeed use the green pump and added 20 ltrs of petrol. In which case the engine was running perfectly on a 66/33% fuel mix. I can't believe that I picked up the green nozzle when I've been using the black one for 38 years.
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Re: Petrol in a Diesel

Post by Oldpug »

I`ve had many HDi`s with petrol in the tank and after draining,new filters refilling with fresh diesel and adding injector cleaner they run with out problems.
Its always realised immediately as they breakdown and wont run so the petrol has only been in the pump a very short while and cant do any permanent damage.
All this strip and rebuild stories are examples of con tricks,get rid of the petrol,fill up with diesel,curse and forget it. Its very easily done though,I have to admit I put petrol in my Peugeot Diesel,very embarrassing!!

The only time stripping and rebuilding HDi fuel systems was necessary was when the pump in the tank failed and sent metal particles all through the fuel system.
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Re: Petrol in a Diesel

Post by spider »

I wonder (apart from the metal particles going around) if the 'fill up with petrol = expense' occurs more for those who have an empty or near as empty tank and then fill with petrol, so there's no derv (of any consequence) to mix with.

When I was in the garage I was amazed at how many cars came in for servicing or MOT etc with the fuel light on, I'd never let it get that low if I could avoid it. To be fair I think we only had one that actually ran out of fuel during an MOT (for which it failed) I can see perhaps "I'll fill after servicing" but running around on some gritty fluid does not inspire.
Andy.

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02 106D, TUD5B, gone but not really missed apart from the MPG
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