"The turbo has gone" (Mazda CX-5)
Discussion
Not mine, it's a 66 plate diesel, 72k, full history, doesn't accelerate beyond 40mph, but no lights or errors.
Mazda say the turbo has gone, which as it starts and drives, but the turbo doesn't kick in, seems like nonsense, as I'd have thought parts of said turbo would have taken out the cylinders. Which it hasn't.
With no codes, it's... Difficult to know where to start. Any ideas?
If it was a blocked DPF (and it does 40 mile round trips a few times a week on the motorway) I'd expect re-gen errors, there are none.
Mazda say the turbo has gone, which as it starts and drives, but the turbo doesn't kick in, seems like nonsense, as I'd have thought parts of said turbo would have taken out the cylinders. Which it hasn't.
With no codes, it's... Difficult to know where to start. Any ideas?
If it was a blocked DPF (and it does 40 mile round trips a few times a week on the motorway) I'd expect re-gen errors, there are none.
If the turbo's gone, the thing won't be producing any compression, so the engine will start and behave fairly normally at low revs when you wouldn't expect the turbo to have much effect, but as soon as you try to build revs and the turbo fails to kick in, you'll get no additional power, possibly borked fuel/air mixture, etc
If you think about it, the bit of the turbo that takes a pasting is in the exhaust side of the system, not the induction side. So if, say, the impeller on the exhaust side disintegrated, it's not going to lob chunks of metal towards the inlet valves.
If you think about it, the bit of the turbo that takes a pasting is in the exhaust side of the system, not the induction side. So if, say, the impeller on the exhaust side disintegrated, it's not going to lob chunks of metal towards the inlet valves.
Edited by ATG on Monday 23 June 23:09
To be honest if you need to ask, maybe letting a mechanic handle this one is best.
Where to start would be checking for play and float on the turbo shaft, making sure it can spin freely when running, checking the actuator and pipework and checking live values are sensible. Basic and methodical step by step troubleshooting.
Where to start would be checking for play and float on the turbo shaft, making sure it can spin freely when running, checking the actuator and pipework and checking live values are sensible. Basic and methodical step by step troubleshooting.
If the turbo has failed the engine would continue to run as normal, just with no boost, the likelihood of anything being ingested is very low. Used to be a fairly common thing on old Toyota ceramic turbos where the shaft would fail, engine would run fine
Not sure of the engine layout but should be fairly simple to access the turbo and use your eyes/hands to confirm
Not sure of the engine layout but should be fairly simple to access the turbo and use your eyes/hands to confirm
OldGermanHeaps said:
To be honest if you need to ask, maybe letting a mechanic handle this one is best..
Well yes, the female owner has been to Mazda who for £150 on their diagnostics has said the £5k car needs £6k of work, their report is basically "no codes so we'd do the following", which is pretty much "replace absolutely anything it could be then the problem will go away".Which has some merit, but is far from sensible economically.
Some further googling shows this
https://www.hella.com/techworld/uk/bi/mazda-cx5-ve...
A defective bypass flap in the turbo might not be replaceable, with other searching suggesting it may not give the P code Hella state, you might get none at all, which is where we are.
Sadly this probably needs a competent garage to do the fault finding, although if it is possible to access this as it shows, it may be Mazda is generally right... Which seems insane z you'd have thought of it is this that would be serviceable, but who knows if people with the skill still exist and can be arsed, when the Modern method really is to just chuck new part at it until the problem goes...
“Turbo gone” could mean anything really. It could simply be a valve, hose or electro-mechanical boost controller, causing the turbo to fail to operate. It’s relatively unlikely to be the mechanical turbo unit itself if it wasn’t smoking, screeching or throwing an error before. That said, variable vane turbos are a bit more complex, and they can seize with age/mileage.
But the bottom line is that as above you have to methodically check everything, starting with the easiest/cheapest and for some of these replacement is the most effective diagnosis.
But the bottom line is that as above you have to methodically check everything, starting with the easiest/cheapest and for some of these replacement is the most effective diagnosis.
macron said:
Which seems insane z you'd have thought of it is this that would be serviceable, but who knows if people with the skill still exist and can be arsed, when the Modern method really is to just chuck new part at it until the problem goes...
It is all repairable, for a lot less than 6KProbably the turbo has seized and you 'should' be able to get it replaced for about 2K (its quite a simple job really if access isn't a pain).
Exact same symptoms on our 407 and that was 1K to fix with a simple turbo swap (but that was about 7 years ago)
Look for a local 'turbo specialist'
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