Sounds as though it was overfilled with oil and it started running on the surplus lubrication oil.

(CONFIRMING SIMILAR ENGINE FAILURE EXPERIENCE, on Mazda 3 Diesel in AUSTRALIA).

Hello from Australia. The engine in my 2007 Mazda 3 Diesel, with only 19,500kms on it, suddenly revved the hell out of itself last year, 2 days prior to me bringing it in for the 20,000km service, and the engine pretty much seized. The final diagnosis by Mazda Australia, after a week long investigation involving fuel and engine oil sampling, came down to this - too much oil built up in the engine, causing (as the forum replier suggested above) the diesel engine to run on surplus lubrication oil. I had checked the engine oil level before and it had indeed gone over the "X" mark on the dipstick (keeping in mind that Mazda's diesel dipstick has its Full mark at the bottom, and X mark further up the top), but thinking the 20,000km service was around the corner anyway, I waited till then to bring the car in for servicing. I was stunned then when the car accelerated like a jack rabbit out of nowhere, the revs hitting 6000rpm and staying there for 3 seconds.

Mazda Australia to their credit did not ascertain blame on me for allowing the engine oil to go beyond the X level, and they replaced the engine. Unfortunately the other major components got damaged as well - the turbo charger and the DPF. All up, including labour costs, the final repair cost was about 95% of the new car price, but I did not end up paying a cent because it was under warranty.

They flashed updated the ECM in the car to fix the problem. I heard from around the traps, that a Mazda 6 in another part of Australia suffered the same fate - both instances, because they were rare, caught Mazda by surprise.

I got Mazda Aust to then write me an official diagnosis and repair report, which they did. My car has been fine since, and the engine oil has not crept up dramatically between service intervals ie. the ECM flash seems to have fixed it.

You may be asking at this point ... "why does engine oil build up in Mazda's diesel engine?" ... well, I asked myself the same question, it turns out their engines are designed with "fuel dilution" as a feature, to burn off the soot in the DPF. This is all controlled by the ECM. To save time explaining it all, read the following article I tracked down on the net ....

http://www.1st-in-synthetics.com/articles/fuel_dilution_surfaces_as_issue_in_some_modern_diesel_engines.htm

I'm not sure what the UK laws are regarding this, but I personally would chase Mazda down for liability, because it's a design fault. Mazda will likely claim it was the owner's responsibility to ensure the engine oil did not go about the "X" mark on the dipstick, but in my opinion every owner is reasonably entitled to believe their engine won't blow up just because the engine oil went above this mark, ESPECIALLY WHEN IT IS BETWEEN SERVICE INTERVALS.

Anyway, it's just pure fortune I stumbled upon this forum (being in Aust I don't always read UK stuff, unless it's about motorbikes!), I hope I've managed to shine some light on all this ... if you can confirm your engine oil went above the "X" mark on the dipstick, I would say this was the problem, and in my opinion, you have grounds to get Mazda to fix it, regardless who serviced it.

Thanks Avant - what do I do if I can't find these last receipts for the 37000 oil change and filter change? Surely my engine shouldn't just capitulate like that in a young car - if there were flaws they would have been picked up at 25000 and the more complete service?

I've looked at the other posts and it does not look promising mind.

I don't think the letter would help you much, because it was (typically and understandably) worded without Mazda Aust so much as admitting liability, but simply stating the problem and what was done to fix it. A legalese would argue they're the same thing, but in my opinion one car's problem does not necessarily mean all cars. And to be honest, with my car still under warranty and the fact Mazda Aust has done the right thing by me, I probably don't want to involve myself directly. I do hope my story has pointed you in the right direction, that was my intention. I would at this stage suggest to do your best (I'm sure you have) to sit back in rational thought and just gather all the technical facts and go from there (legal wise). I haven't been able to work out what your car service history is, but if it can be shown it was serviced (ie. oil changed) according to its intervals, I think that's a fair basis to come to some sort of repair agreement with Mazda - as one replier suggested, there is no such thing as a false deadline, that's just corporate bullies using every trick in the book to hold off or dismiss a valid claim. Stick to your guns, be cunning with your plan, and go from there - I find it hard to believe the UK will not have a consumer affairs watchdog to take up your case. If worse comes to worse, consider contacting a TV station's current affairs program with your woes - I'm sure there are enough Mazda 6 diesel owners out there to add to your voice! The last thing Mazda or any company wants is negative publicity ....

How did you pay for the 37,000 service?

Credit/debit card or cheque will be sufficient for the bank to prove payment. Cash will have no record.

That's probably what caused the engine to fail - normally the rev limit on a diesel is below 5000 (mine starts at 4750 and is red-lined at 5000)

Did you see my x3 trouble post. you see this is what Im having. The engine was over its limit with oil. My husband used some kind of gadget to suction some oil out- nearly a litre.

Im not making excuses but a motorist should not NEED more than a basic understanding in order to buy a car. It certainly is a benefit to know one end of an engine from the other BUT should not be a requirement. Most people probably know to check their oil and put air in their tyres. Some will know how to carry out various maintenance jobs, replacing brake discs, pads and rebuild their suspension, but I do not know of many people who have a full diagnostic kit for each car they own to check every single snivel the car makes. i should not NEED a degree in the engine of each car i own in order to be able to own it and drive it.

We've all heard the story of the winnebago driver who engaged his cruise control and went out back to make coffee leaving the steering wheel unattended wrote off the vehicle and NOW the handbook says DO NOT LEAVE YOUR SEAT as a result. If modern diesels are only supposed to be driven more than x amount of miles and any less will result in a full engine failure then surely you should be told somehow?

There are 4 lines in my handbook about the dpf. thats it.

Ok ill climb down now. good luck vanillaslice.

Thanks to everyone for their help, it's not looking so good. It turns out the 37000 is not even an issue as they are not willing to accept the 12000 anyway - when I didn't own the car. The reason I am having the difficulty finding information on the final one is because I had the guy that I bought it off put it through, the people that did it have gone belly up due to recession I presume.

The main problem I am finding is actually getting in touch with Mazda - I was left a voicemail telling me that I had until 12am on Thursday past to provide evidence or else - tough. I have been trying to phone ever since and all I get is a voicemail with no option of leaving a message - never heard that one before.

The really annoying thing is that, while I can appreciate the warranty stance - even though the car is very young - there was a re-call for my car with the exact problems that I ended up experiencing - Mazda never informed me about it and the dealership never changed my name at the 25000 mile service to allow me to find out about it. Top this all with the fact that my 1 year old was in the car at the time the thing happened and found it acutely upsetting. I have decided that my next step is to seek legal advice - I'm sure this will go on for months and it does not help that I have no car to get to and from to work though.

One thing is for sure - I'll not be buying Mazda again and I'll be telling everyone tha tI know the same thing.

Thanks again for all your extremely helpful advice. This is exactly the kind of forum that more people need to know about.

Michael.