Are you getting a check engine light?

I have a 2010 3i sedan with 179K miles, 2nd owner since 2013 and 33k miles, and no, I haven't had a timing chain replaced. But I did have 1 snap on me, a chain, in my bought-new 1994 Toyota DX 4x4 pickup with about 148k miles. I've also had an old 1987 Subaru DL 4x4 wagon that would regularly snap a timing belt every 30k miles. A Toyota mechanic told me the timing chain guides were made of hard plastic and wore out. And the engine was interference and trashed my just-recently-replaced rebuilt cylinder head! The Sub was non-interference, and I replaced a timing belt and drove again.

In both cases the vehicle just shut down, stopped while driving and would not restart, had to be towed from scene. They did not limp home. They were immediately un-drivable.

I think you need more diagnosis. There's a lot of things that could cause a no start but normal crank.
You did hear some "clunking noise" apparently when things happened. Perhaps the variable valve timing control system or actuator went out of whack. There's a procedure to check that in the shop manual. Especially the actuator, where it shows looking at 1 gear(actuator) on the end of the camshaft. There are notch marks on the actuator's cover and rotor that should be lined up. The actuator has a cog driven by the timing chain.

I'm not sure your interest or time for diagnosing on your own. Of course if it's not feasible, who then for a mechanic? Especially where it has to get towed. Always fun getting that right. I have a Mazda dealer I like for when the going gets rough. But, not always the case to find one, is it?

If you can do some things, you need a genuine Mazda shop manual for your year. And I might look at doing a compression test. Then I might look at the variable valve timing control system test.

I any case, from my manual, here's a copy and paste of the summary list of things no start could be. I focused on the last 2 on the list. The genuine manual has all the system sub-sections that go into detail, and has those 2 tests I mentioned spelled out. Still have to be enthused and mechanically-inclined. Mostly enthused:

 

Thank you Brian for the long reply.
some interesting notes there.
I did get it towed to a garage that my wife and I have used, but after extensive work, he couldn't find the problem.
So back to square one. He has charged me a lot of money (mostly labour).
changed the spark power packs. The ECU, and a few others, but still at a dead end.
after he kept asking ME what to do, I lost confidence in him.
I now have another old work guy looking at it, who suggested it could be the timing chain, loose one, slipping a cog or two, hence the clunking noise I first heard,?
I've left it with him for now and see what he comes up[ with.
In hindsight, I may have had it taken to a Mazda dealer.
But many thanks again for spending so much time with me.

 

Typically when a timing chain goes out it renders the vehicle immediately inoperable so if it went into lyymp mode and you drove it home it's probably something else

 

I can guarantee if the timing chain jumped a tooth or two your check engine light would be glowing. So, has anyone pulled or checked to see what codes are showing? Paying mechanics to guess will cost you lots of money.

Is this automatic or manual transimssion, if auto could it be transmission is in limp mode, just a wild guess here.

 

Mike has a good point about auto transmission possibly. Something could have "clunked" internally there while driving and maybe that's now interfering with ignition. See if you can get various cel codes back from the shop. I don't have an auto trans myself, so I don't know, but I think there may be a separate tcu(transmission control unit) that could be scanned for codes specifically on the auto trans?
Having these codes and posting them, might bring others into the conversation.

 

I can guarantee if the timing chain jumped a tooth or two your check engine light would be glowing. So, has anyone pulled or checked to see what codes are showing? Paying mechanics to guess will cost you lots of money.

Is this automatic or manual transimssion, if auto could it be transmission is in limp mode, just a wild guess here.

its manual transmission Mike. What do you mean by Engine light glowing

Mike has a good point about auto transmission possibly. Something could have "clunked" internally there while driving and maybe that's now interfering with ignition. See if you can get various cel codes back from the shop. I don't have an auto trans myself, so I don't know, but I think there may be a separate tcu(transmission control unit) that could be scanned for codes specifically on the auto trans?
Having these codes and posting them, might bring others into the conversation.

Unfortunately the guy who charged the earth trying to find the fault didn't give me any info on the ECU he just replaced it with a used one.
I'm just waiting to hear back from this other mechanic (who I left the car with) He was the one who suggested it could be the chain etc.
I don't hold out much hope of it being sorted anytime soon.

Thanks for the replies though.

 

just thinking again.
What would you guys do with perhaps buying a used Engine?

 

by glowing I mean is the check engine light on?

 

Ah sorry.
There was just an orange engine management light on, if that's what you mean?

 

well, anyone tell you what codes it is throwing. I guarantee if the timing chain jumped a tooth, you will have a check engine light and a code or 2 or 3. If it jumped more than a tooth, you would bend some valves. Seems odd that neither of these guys can do a diagnosis to at least narrow down the issue.

I'd find what the issue is before I considered buying a used engine. Lots of labor to swap out an engine unless you can do it yourself.

 

You’re in the UK? I’m sure we don’t always appreciate the idiosyncrasies of doing what we do, integrating pro or auto parts store diagnostic code reading, being nimble around all that with choices , vis a vis over there.
I agree essentially with Mike.

I think maybe having a pro 1) check the codes, 2) check engine compression and 3) popping off the valve cover to look at the top of the valve train- the timing chain, the 2 cogs attached to the 2 camshafts driven by the timing chain. One of those cogs has a thing called an actuator that is adjustable and inspectable and may have in fact slipped- all this inspectable without declaring timing chain slipped or gone. But certainly a good mechanic lifting the valve cover to look there would be able to tell a lot about the chain state.
Their doing #s 1 and 2 should lead there. Especially the compression test. Because if things are busted in the drive train and valve train and within the cylinders and head, a compression test can deduce a lot of that.
Worst case probably or reasonably is like my 1994 Toyota. It’s an interference fit cylinder head, chain slipped enough or snapped and the cylinder head and valves were trashed and the head will need rebuilding or a swap out.
That maybe, pulling out my ass a bit, but adjusted for inflation from 2003- maybe a $3000 job in US.
I had to do it 2x within a year on that stupid 1994 Toyota. And it was like $1100 and then $1300 then I recall. First time overheating. 2nd time timing chain guides wore under the first replacement. And the timing chain started slapping around and snapped.

 

well, anyone tell you what codes it is throwing. I guarantee if the timing chain jumped a tooth, you will have a check engine light and a code or 2 or 3. If it jumped more than a tooth, you would bend some valves. Seems odd that neither of these guys can do a diagnosis to at least narrow down the issue.

I'd find what the issue is before I considered buying a used engine. Lots of labor to swap out an engine unless you can do it yourself.

well, anyone tell you what codes it is throwing. I guarantee if the timing chain jumped a tooth, you will have a check engine light and a code or 2 or 3. If it jumped more than a tooth, you would bend some valves. Seems odd that neither of these guys can do a diagnosis to at least narrow down the issue.

I'd find what the issue is before I considered buying a used engine. Lots of labor to swap out an engine unless you can do it yourself.

 

Well, new call from the mechanic its with right now.
He says htat he found an oil overoad, which can cause the smoke emision. He took out 32 or 3 quarts.
He had to order a compresion tester ads the one he has is the wrong size. He said it is a 14mm fit, which he hasn't got.
He really wants the existing ECU, which I don't have, from the original guy who I wasn't happy with, but said to wait and see what the compression is like.
So far it does look like the first mechanic I used got it all wrong. ie changed parts Willy- nilly if you see what I mean.
Just waiting now.
Thanks again for your input Mike.

Edit.
Also could see the timing chain, which wasn't very loose.

 

A timing change doesn't suddenly go bad at 57k miles - I'd expect 100-120k miles if oil is properly maintained. A timing chains stretches and get noisy before it eats the plastic guide or jump a tooth. A timing belt goes maybe 75-80k.

 

OK guys. I now have a usable M3 again.
the New mechanic took off the rocker box, and checked the spark plugs and power packs and comresions. Then checked and cleaned the crank sensor( I didn't know what that was until he told me, lol) I looked at the chain, and it and itwasn't too loose, so he didn't worry about that, He did take 3 litres of oil out of it though (not sure how that got in, can only blame the originol engineer for that) He took it for a test drive and said he was quite happy with it now, I also drove around the block and it went very well. So hopefully that's it (fingers crossed). still not sure why it played up in the first place, though. all that trouble with the first guy who cost me my arm & leg
Once agin, thanks for your time.