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2015 Forester Diesel DPF light flashing

15150 Views 2 Replies 3 Participants Last post by  Alternate
Hi. My Forester has had the DPF (flashing) light come on. I have reset the Oil Dilution. It is approx 5000 ks to the next service. Should I ignore or change the oil and filter now. The car has travelled 86,000km. This has also happened before the last service and the scan reported that the DPF filter was ok, but oil dilution was the cause. Any help appreciated.
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sorry for late reply. Some comments:

0) You need to determine exactly why the light is flashing. The reason (if I remember rightly) may not only be an oil dilution issue. Get the OBD-II code read out by someone, or get your own device and do it yourself. It's easy nowadays- just look online.

1) You're a 2015 so IFF (if and only if) the car is still covered by a new car warranty then DON'T do any of your own work or the warranty may be voided.

2) If you're coming to the end of the warranty period have the car professionally inspected by an independent mechanic and have Subaru fix all of the issues.

3) Even if you are outside the warranty period, Australian Consumer Law consumer guarantees apply (beyond warranty) and that provides protection for ". Have a look at the Fair Trading site for your state, you may be surprised at what you're entitled to. However getting car manufacturers to comply is another matter. I think Subaru can be one of the better ones. Be firm, reasonable and quote the ACL at them.

4) As for the oil change, if it is dilution you need to find out why as the dilution is a symptom of an underlying problem (see 3 above) . You need to find and fix that problem. Take advice from your specialist diesel mechanic or Subaru dealer. Mine was quite reasonable once (I think about 8-9k out of a 12.5k service interval) , they said the oil was Ok, reset the dilution and told us to continue to the service interval.

5) An oil and filter change won't hurt, but again check your warranty status.

6) Remember: an aftermarket DPF will (probably) cost (min) $2.5k fitted + parameters recalibrated/reset to match. An inspection will cost (say) $200. A code reader (say Torque Pro and a Dongle) $50 for a cheapie, $200 for an OBDLink. A mechanic oil change (and code read/reset) say $200. So for the risk of a new DPF you can get :
- 12.5 professional mechanic oil changes, or
- 12.5 good code readers (and which can be used and apply to any Oz car post ~2005 petrol and ~2007 diesel), or
- 12.5 inspections
- or 12.5 of any of the items above

7) A good diesel mechanic will go beyond the oil reset.They'll be able to read out and tell you any other underlying issues, e.g. injector trim parameters, suction control valve behaviour, fuel rail pressure behaviour, turbo/boost performance, EGR, DPF, sensor behaviour, etc, etc.
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Hi Forester109. What are your driving habits like?

I have a 2015 Diesel Foz also, and I am having similar (if not the same) flashing DPF light issues. If it's going straight to flashing, then likely to be oil dilution. If you have to reset the counter I would certainly be changing the oil. The first time mine was flashing the oil level was about a centimetre above the full line.

Great advice from pitrack_1, I would definitely get on to the OBDII scanner and confirm your suspicions first before going any further. I bought one off ebay and used the Torque app.

Would certainly recommend finding yourself a comfy chair, make your self a cup of tea/whiskey and read his other thread. Especially where he goes into detail about his Torque dashboard set up. It's perfect for monitoring what your car is up to.

In the end, I've resigned to the fact that our driving habits just do not suit the Diesel Forester. The post injection regeneration method it does imo is idiotic, and the vehicle just doesn't have a chance to evaporate the diesel out of the oil before it's performing its next regeneration. At the rate we were going, the Forester would have needed an oil change twice in between every service. We ended up buying a little car for around town, school runs, shopping trips etc. The Forester is now a holiday/weekender/boat tower which suits it much better.
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