Mazda 6 2010 2.2 Diesel Died

[dabbler]

A long post, im hoping someone could advise me please? Very much appreciated - thankyou.

My 2010 Mazda 6 2.2 diesel has now done 150,000 miles. Last year, the timing chain stretched - i had a quote and it was in the thousands, so i did it myself and the car has been great for 1.5 years.

At the end of the summer, the aircon stopped working (hot air only) but i left it as i would address the compressor or clutch at the next service (in two weeks time)

A few weeks ago, the car started making a "rattling" sound from the engine bay, it wasn't the usual timing chain banging / loud rattle sounds when they go, but more of a "screws in a tin can thats being rotated" type noise. I sought advise and was told this was probably the aircon clutch, so i left it as would be servicing in in a couple of weeks.

On our way home today, there was a loud clunk and all power to the engine failed. Upon inspection, the aircon clutch is spinning feely and not affecting the serpantine belt - so i dont think thats the issue :-( (I was hoping it was)

The engine does turn over, but will not start (it doesn't even try to fire). There is a deep thud from the engine when it is rotated. It sounds light, like a lack of compression.

Does any one have any idea what the cause maybe or what i should check? Ive connected up the old ODB2 diagnostics, and the list of error codes is in the pages long. (DPF Regen cycles too high, Crack Sensor Range, EGT Sensors low, Intake manifold air control actuator, fuel shut off valve open circuit, right front tone wheel, EGR circuit malfunction)

An awful lot of codes.

Any thoughts please? Could it be the whole lump has died? Ive heard horror stories of chains going, injector seals failing leading to blown turbos etc etc.

The car is only worth maybe £2k now, so i dont want to go down the rabbit hole of replacing parts and spend more than its worth,

Thanks for your help!

[dabbler]

Just went to take the rocker cover off to check, before i did that i took off the oil cap - i can see rockers, no movement at all when the engine turns over and a god awful metal rattling sound.

does any one know if this engines valves can be damaged by a broken chain etc?

[apav]

I had written the answer below but you replied before I posted.

It is gone I think. A new chain kit as parts will cost you more than you sell it as scrap or sell parts of it. If you sell some parts within the new weeks and then sell the rest for scrap, you will make more money than risking starting a repair which you do not know whether it will work out.

Here is the answer I had written:

When you described the noise as rattling, I would expect to find the deep thud you find now. Such deep thud usually means bearings of some sort in the engine.

Are you sure that the timing chain has not died? Do the diagnostics read the timing chain angle without the engine running?

I think the codes you read are not directly connected to your current problems. It is more likely that these codes accumulated over the years but the car was still driving. Maybe if you disconnect the battery, some of these will clean up.

As you did the chain, you can DIY remove and clean the sensors. If the sensors are cheap, you can take the gamble and buy them. But it sounds like you have a mechanical problem rather than an electrical problem. I think the deep thud can only be fixed if you open the engine and find out what is going on.

Can you trace how many chains this engine had over the years? Maybe the engine is worn out and it is beyond repair.

I am not sure if the car is worth £2K. If you do an Auto Trader valuation, you may be surprised that you will get less than £500 for part exchange and less than £1,500 for a private sale. Buying a used engine will cost you that much. So I am not sure whether you can do the man maths and justify it.

You should try the scrap companies to find out how much they are paying for the car as it is or advertise it for breaking and sell off the parts by yourself. My guess here is that if you advertise a few parts and manage to sell them, you will sell them more than the scrap value.

Also, you ask a mobile mechanic to come and have a look at it. A 5 mins check to let you know what is the course of action and how much it will cost. I guess that a guy can turn up and give you a quote for free. So that is a free option before buying sensors, etc.

My guess is that the engine has run without sufficient lubrication and it wore out. It is not simple to DIY it as it stands and it will cost real money.

Maybe your best bet is to confirm with a mechanic what the car needs and how much it will cost for a start. Whatever they tell you, it may increase very quickly if they start doing works. Then figure out how much you can sell it as scrap or sell it partially as parts and then sell the rest for scrap. You can buy a newer and less mileage 6 for less than £2K on Auto Trader. So if you manage to get £500 of your car, you may need an extra £1K or just over it, to have a newer and lower mileage car to move around. If that £1k or so is that all the extra pocket money you need to have a car running, you should seriously consider giving up hope for your car and getting a new one. Each wheel will go for £50 on ebay, plus selling doors, bumpers, seats, lights, etc, will get you that £500. That is why scrapping companies pay a bit extra. You just need to do your homework because you cannot make the car start as it is. So it is tricky to decide what to do next.

[dabbler]

To add, just removed the air filter and virtually no suction into engine. Also virtually no air out from the rocker box cover.

[dabbler]

I had written the answer below but you replied before I posted.

It is gone I think. A new chain kit as parts will cost you more than you sell it as scrap or sell parts of it. If you sell some parts within the new weeks and then sell the rest for scrap, you will make more money than risking starting a repair which you do not know whether it will work out.

Here is the answer I had written:

When you described the noise as rattling, I would expect to find the deep thud you find now. Such deep thud usually means bearings of some sort in the engine.

Are you sure that the timing chain has not died? Do the diagnostics read the timing chain angle without the engine running?

I think the codes you read are not directly connected to your current problems. It is more likely that these codes accumulated over the years but the car was still driving. Maybe if you disconnect the battery, some of these will clean up.

As you did the chain, you can DIY remove and clean the sensors. If the sensors are cheap, you can take the gamble and buy them. But it sounds like you have a mechanical problem rather than an electrical problem. I think the deep thud can only be fixed if you open the engine and find out what is going on.

Can you trace how many chains this engine had over the years? Maybe the engine is worn out and it is beyond repair.

I am not sure if the car is worth £2K. If you do an Auto Trader valuation, you may be surprised that you will get less than £500 for part exchange and less than £1,500 for a private sale. Buying a used engine will cost you that much. So I am not sure whether you can do the man maths and justify it.

You should try the scrap companies to find out how much they are paying for the car as it is or advertise it for breaking and sell off the parts by yourself. My guess here is that if you advertise a few parts and manage to sell them, you will sell them more than the scrap value.

Also, you ask a mobile mechanic to come and have a look at it. A 5 mins check to let you know what is the course of action and how much it will cost. I guess that a guy can turn up and give you a quote for free. So that is a free option before buying sensors, etc.

My guess is that the engine has run without sufficient lubrication and it wore out. It is not simple to DIY it as it stands and it will cost real money.

Maybe your best bet is to confirm with a mechanic what the car needs and how much it will cost for a start. Whatever they tell you, it may increase very quickly if they start doing works. Then figure out how much you can sell it as scrap or sell it partially as parts and then sell the rest for scrap. You can buy a newer and less mileage 6 for less than £2K on Auto Trader. So if you manage to get £500 of your car, you may need an extra £1K or just over it, to have a newer and lower mileage car to move around. If that £1k or so is that all the extra pocket money you need to have a car running, you should seriously consider giving up hope for your car and getting a new one. Each wheel will go for £50 on ebay, plus selling doors, bumpers, seats, lights, etc, will get you that £500. That is why scrapping companies pay a bit extra. You just need to do your homework because you cannot make the car start as it is. So it is tricky to decide what to do next.

Thanks for the reply. Do you know if any valve damage could have occurred in these engines?

If a tensioner or cog has gone but no damage to valves I may replace it.

Here is a video through the oil filler cap:

https://youtu.be/m63GC-g2em4

[apav]

No I have no idea how the valves are affected by the chain.

But how does the engine turn and does not start?

From your video, there is something loose inside the engine?

Are these chain kits starting from £250 without even being complete?

I really do not think you should take the gamble.

Imagine that with £250+ you have a new chain kit DIY fitted.

What are you going to do with all other error faults you got from the reader?

It sounds like a big step to the unknown.

If you have a local car auction, you can buy a running car for not much more than the parts you will have to invest in yours.

This indicates that something is going wrong here.

You already had one chain fitted and now you do not know whether a new chain will fix your problem and have the car back on the road.

Most of the people nowadays will scrap a car for needing tyres and discs for the MOT because the garage will charge them some good hundreds.

Doing a second chain in an engine that sounds like that, I think it is on the optimistic side that you will get away for another year or so.

And it is not that these engines keep going for ever. They have some bad reputation.

And that is the worse with these cars because they wear their years quite comfortably but their weakest point are the engines.

[dabbler]

Thanks for the reply - i had the rocker box cover off today, all the lifters have been smashed off, the cog at the end of the camshaft has sheared off and wobbling around! An initial quote was 2.5k for a independent to fix. Ill strip off the timing chain cover soon and see what damage if any if there. From my understanding, there may not be valve damage as its designed for the lifters etc to be destroyed - hence saving the valves.

So it (if lucky) all it needs is Camshaft +Lifters, Another timing chain and injector seals. Not 100% sure what ill do, but the independent i spoke to was very helpful and for £60 will take a look at it. Problem is getting it to him...

[apav]

I think you are in a hurry. Try to take a step back and reconsider the whole situation.

How much did you pay for the car? I had bought mine for £4.5K at 6 years old from the dealer with the history and the timing belt done, at 76K miles. Paying £2.5K to rebuild a fragile engine with 150K miles on it does not sound very wise. The same dealer has a 2008 diesel 6 now for sale for £3K and it is a 64K miles car. If you pay £2,500 for the repair, sell your car for £500, catch the next train and buy the one from the dealer with some warranty.

https://www.arnoldclark.com/used-cars/mazda/6/2-0d-s-5dr/2008/ref/arndl-u-10665

A camshaft, plus the seal and the sensor, will not come cheap. You can easily throw £200-£300 here.

Another £200-£300 for the timing chain, water pump, auxiliary belt.

Another £50-£100 for the lifters and anything minor extra to close it up.

Plus the £50 to the guy to confirm what is going on.

Plus the injector seals, plus transport, plus, plus, plus.

You have paid easily £500 before you start rebuilding it. I think you have to be realistic and expect that will be closer to £1,000 as a final cost to DIY the work. But if you end up transporting the car to the garage, you are already almost fixing it there. So you will end up with £2,500 gone.

Price up the parts that you already know that you are going to buy and all other costs like the garage, the transport, etc, then call the scrappers and find out how much they will pay for it. Similar cars are on sale on Auto Trader from £500 for non working cars like yours.

My guess is that your particular engine will not last very long, even after a very careful £2,500 rebuilt by a professional. There are so many GH cars which had multiple chains one after the other, without breaking up like yours. Your engine will have tolerances far beyond the original engine. So I think that 1-2 years later you will be back on square one.

If you can get somebody to come over to your home and check the car, give that £60 or whatever they ask, to keep your mind in peace that you tried.

https://www.whocanfixmycar.com/

As I said before, they may come around to have a look for free.

If they give quotes in thousands like the £2,500 quote you already have over the phone, think very seriously whether this is the right way forward. The 2.0 belt engine will keep going for ever compared to what is going with the 2.2 chain version of the same engine.

If I was you, I would advertise it on Auto Trader for £500. I expect that you can get £250 for scrap value. If you manage to sell for £500, you save yourself the trouble of having to break and sell the car bit by bit.

I would use the £2,500 for the repair to buy another car from a franchise dealer. If you want to buy another 6, you can buy another for not much more than the £2,500 repair bill as you can see from the ad above. I would not trust that entering the garage for £2,500 you will not end up driving out with a higher bill.

If you end up buying another 6, you can keep yours for parts.

If you decide to buy another 6 from an independent dealer, keep in mind that most of these cars are part exchanges which cannot be sold at the franchise dealers because of the faults they come with. Faults include the regular maintenance needed to keep it going and which costs a bit too much for the dealer to guarantee and sell them. So they sell them at the auctions for £500, plus auction fees, plus transport, the £500 becomes £1,000, and then the independent dealers double that price and wait for the sale. There is a chance that bailing out of a £2,500 and buying a £2,000 independent dealer car from the auction, may bring back at the same position and the extra £1,000 to buy a franchise car is better value for money.

Anyway, I do not want to destroy the spirit. I can see that you are happy for DIY and by all means give it a go. Even if you pay £500 for parts and then sell the whole car for similar money, you lose very little. But what I would not encourage is a £2,500 engine repair even from an engine specialist. It is just a bit too much to risk. Sleep on that and gather more opinions and information before you commit in anything.