You'll need to get readings from the computer so you know what the status of the DPF is. No way of knowing anything at this point. It could mean your DPF is clogged by the previous owner and they did no want to deal with cleaning or replacing the DPF, and did not disclose that information when they sold it. Or it could mean something else is gone wrong with the DPF. Such as the previous owner purposely drove short distances everywhere and never gave the DPF enough chance to get hot enough to regen.

But you stuck without getting a proper computer reading of the status of the DPF. So start there.

 

Between posting and your reply (thank you) I did some searching.

That lead me to oil dilution. I have no service history but the engine oil looks clean. It was always been my intention to do an oil and filter change before long with it being unknown.

So I did an oil dilution reset. That has cancelled the flashing DPF light.

Am i safe to go ahead and change the oil and filter and just see how it goes with the DPF light? What does a subaru dealer charge to check something like that? Can my more friendly and cheaper independant garage with a Clip On diagnostic kit do anything useful by way of finding error codes?

I take it my cheap DIY ODBII code reader is of no use here?

 

Where are you based in the uk.
Theres an independent specialist I know that would give good advice over the phone.

 

I am in the Highlands 20 miles north of Inverness

Just tried my cheap basic code reader. It has 1 code showing, P1468 $07e7 Manufacturer Control.

I have not tried resetting it.

 

@ProDave Sorry can't be of more help. I am in the US and we never got the forbidden fruit from Subaru. My experience with diesel and DPFs have been from the VW and MB diesel world. I use to own the 2012 Jetta TDI, 2011 VW Touareg TDI and 2013 MB ML350 Bluetec. Enjoyed everyone of them. My regret was turning in the 2011 VW Touareg TDI, I should have kept it and taken the money from VW during the diesel gate.

 

Your DTC P1468

Attached is the maintenance mode info - "oil maintenance" and "DPF regeneration" procedures when using Subaru Select Monitor. For MY09-12.

 

So in simple terms is it safe to just change the oil and filter, reset the oil dilution (again) and see how it goes? Or is that wishful thinking?

 

No more replies so I will summarise my understanding of the DPF system is as follows:

In normal operation it will burn off the accumulated soot automatically without even telling you. If you do too much short slow driving it will light up the DPF light as a gentle reminder to go and take it for a blast to let it burn off the soot. If you ignore that, it will later start to flash the DPF light to basically say it's too late, take it to your dealer for them to force a regeneration.

That bit all makes sense and is in the owners manual.

The bit that is NOT in the owners manual and what caused all the confusion is the DPF light has a dual function, to warn you when the oil dilution gets too high and you urgently need an oil change. When that happens it goes straight to a flashing DPF light. So the unsuspecting owner like me opens the manual and gets told to go and see their dealer and expecting it to be something serious.

I think it is VERY poor to have this dual use of the DPF light made even worse by no mention of it in the owners manual.

It would be far better in this oil dilution situation to flash a different light, how about the oil warning light, and state clearly in the manual what the flashing means.

I have done my oil change, reset the oil dilution counter and cleared the DTC. Lets hope that is the end of it and everything works normally from now on.

the oil did not look bad so my suspicion is the previous owner changed the oil but did not reset the oil dilution counter. But better to be safe with fresh oil and filter.

 

Did you ever sort the issue? I have a similar issue in my 2013 diesel XV (same engine).
The DPF light was blinking, it stopped after a couple of motorway runs, then started blinking again but didn't get the chance to take the car for a blast for a few days, today I drove for 2hrs at 2.5-3k rpm but it didn't clear so I took it to my Subaru specialist for a forced regeneration. Soot showed 41%, we did 2 regenerations, quite a bit of black smoke came out of the exhaust, the soot dropped to 4% but the DPF light would stay flicker in the cluster (we couldn't find the error code). Doing a 3rd forced regeneration as I type this and now I observe soot has increased to 36% on the OBD diagnostic tool. Not sure what to do.

 

In a perfect world oil dilution shouldnt be a problem at all, since the percentage drops as the car is being driven and regens don't occur often enough to rise it again.
I have done almost 20k km since I last reset OD on mine and I'm now at 1.4%