Mazda 3 2010 turbo diesel - mystery fault.. please help!

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Tue 9 Oct 2018 00:37
Mazda 3 2010 turbo diesel - mystery fault.. please help! - Wendy Bradshaw

This could be a bit of a long post but i will try to keep it as brief as i can.

A couple of weeks ago my beloved Mazda 3 1.6ts diesel...died on the motorway It was towed to a local independent garage, where £800 later the turbo was replaced, the dpf was filled with fluid and regenerated and oil + oil filter replaced.

It ran ok after that for about 2 days... then the dreaded limp mode began.. with MIL light on and an odd amber jagged circle with ! in the middle (which i can't seem to find when googling Mazda warning lights)


The slug car went back to the garage to be checked, they plugged the diagnostic in again and the problem showing was the dreaded DPF (code P242F)


They attempted a regeneration AGAIN but when they came to the final stage of the process, the computer wouldn't allow the regeneration, saying the car does not have a DPF!! I'm not even certain the DPF is the issue as no DPF warning light has ever come on the dash but i guess the code would contradict that ??


I am now left with a car that is just about driveable, in limp mode, not revving above 3000rpm or going above 60mph. It also takes far longer than it should do, to gain speed at lower mph and my local garages haven't a clue what to do with it. 3 different 'professionals' say they've never seen anything like this before.


It is booked in, to go to the Mazda dealer next week, but before then i would really like to try to resolve this before i get whacked with a ridiculous bill that quite frankly i can't afford
I would be grateful of any help at all!

Thankyou

Edited by Wendy Bradshaw on 09/10/2018 at 00:39

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Tue 9 Oct 2018 09:05
Mazda 3 2010 turbo diesel - mystery fault.. please help! - hardway

"the dpf was filled with fluid and regenerated"

that might work but seems to have not,

probably the only real cure is remove the DPF and have it professionally cleared/cleaned.

Try Googling "DPF doctor" and see if you have anyone local.

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Tue 9 Oct 2018 13:13
Mazda 3 2010 turbo diesel - mystery fault.. please help! - Gibbo_Wirral

They attempted a regeneration AGAIN but when they came to the final stage of the process, the computer wouldn't allow the regeneration, saying the car does not have a DPF!! I'm not even certain the DPF is the issue as no DPF warning light has ever come on the dash but i guess the code would contradict that ??

They're probably using some generic work-on-almost-anything diagnostic tool, which isn't working properly.

Can you give us any more details as to why the car died and why parts were replaced?

And can you give a bit more detail on the car - mileage, what sort of driving conditions it does etc.

Like Hardway says above, my guess if the DPF is blocked.

Edited by Gibbo_Wirral on 09/10/2018 at 13:15

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Thu 11 Oct 2018 03:22
Mazda 3 2010 turbo diesel - mystery fault.. please help! - Wendy Bradshaw

hi.. thanks for your reply. the car has 80k on the clock and admittedly I do do alot of short trips but do try to get the car out on the motorway once a week to regen the dpf.

the garage claimed to have cleaned the dpf but my guess is they didn't :/

they said the car had died because the pipe to the turbo was blocked..and the oil wasnt getting to the turbo.. therefore needed replacing?? and the fault code also said the dpf fluid had run out and the dpf itself was blocked so they were supposed to have put the dpf PAT fluid in, and also 'flushed it out' ..

now as you can tell..I'm pretty much a novice so I'm not sure if what they've told me is true.. I know the turbo was replaced because I can see that but as for the dpf work, I don't know if they've done any work to it at all :/

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Thu 11 Oct 2018 06:40
Mazda 3 2010 turbo diesel - mystery fault.. please help! - hardway

DPF is basically a soot collector,

and eventually it fills up,

inside is a very fine mesh and yours is blocked up,

Manufacturers diagnostics can initiate a DPF purge/clean but can only do so much,

A regen is definitely the first step to cure this but your DPF is beyond this.

I don't doubt your garage tried this and did all they claimed but if the DPF is that blocked it wont work.

The DPF most likely either needs renewed or sent off the a DPF specialist.

they basically "cook" the unit in an industrial oven to burn off the soot.

Google DPF doctor for more information,

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Thu 11 Oct 2018 08:54
Mazda 3 2010 turbo diesel - mystery fault.. please help! - craig-pd130

I second Hardway's post - it seems you've had two separate problems. The turbo problem, and a DPF full of the ash residue from the soot that has been burned off over the car's lifetime. This is what eventually kills DPFs because the ash cannot be burned. Depending on the car and usage, DPFs can need replacing at 70 - 80,000 miles.

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Thu 11 Oct 2018 12:36
Mazda 3 2010 turbo diesel - mystery fault.. please help! - Engineer Andy

I second Hardway's post - it seems you've had two separate problems. The turbo problem, and a DPF full of the ash residue from the soot that has been burned off over the car's lifetime. This is what eventually kills DPFs because the ash cannot be burned. Depending on the car and usage, DPFs can need replacing at 70 - 80,000 miles.

If, as the OP says, they do a LOT of short trips from cold, then the DPF could fail (terminally) again in short order, far sooner than another 70-80k miles. Personally, I'd sell the car after its been repaired and get a petrol-engined equivalent. No turbo (on the equivalent gen-2 Mazda3 [any modern, non-MPS Mazda petrol doesn't have a turbo]) and no DPF to go wrong if you want to stick with Mazdas (my 1.6 gen-1 is still going strong); lots of decent alternatives (petrol) out there as well.

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Thu 11 Oct 2018 13:37
Mazda 3 2010 turbo diesel - mystery fault.. please help! - Gibbo_Wirral

they said the car had died because the pipe to the turbo was blocked..and the oil wasnt getting to the turbo.. therefore needed replacing??

Ask them if they also did anything about the blocked turbo oil feed pipe and filter.

Is it possible the wrong oil has been used on the car for some time (and / or infrequent oil changes) and caused both problems?

Edited by Gibbo_Wirral on 11/10/2018 at 13:38

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