Hi everyone,
I recently bought my first Subaru and my first diesel. It’s a lovely, smooth car to drive and it’s a BEAST, but it turns out it’s also a bit of a princess.
It’s a 2016 Subaru Outback turbo diesel. I bought it second hand and it had only done 40,000 km over 7 years so I thought it was a bargain. After 3 weeks, the DPF light came on. It didn’t go solid, it went straight to flashing. I took it to the subaru mechanic and they said it just needed an oil change. This was when I learned that diesel engines don’t like suburban driving. They like long drives on the highway.
Luckily, I do most of my driving on the highway, which is why I bought the diesel.
Two months and about 5000km later, it happened again. The DPF light went straight to flashing. The oil level was high and apparently the car has been trying to regen but aborting. The mechanic says it’s my fault because I’m not driving it properly. I’m braking too much, not getting the engine hot enough, and not doing long enough trips.
But that doesn’t seem right.
According to my car log book, 78% of my km’s are work trips. This means 30mins of driving at 100k/hour with steady throttle and not breaking unless someone stops suddenly in front of me twice per day.
The stats the mechanic gave me are:
Oil dilution too high - 15%
DPF condition good
Ash 23%
Soot 21%
Regen attempt 503
Completed 171 (averaging out to every 90kms)
The mechanic says that every time the car tries to regen, it puts diesel into the oil to make it hot enough to burn off the diesel particulates and that’s why the oil gets diluted. She says the way to fix it is I have to ‘teach’ the car to regen only every 200km and then make sure that regen attempt doesn’t abort. I have to get the engine hot, by letting it run in the driveway for up to 10 minutes, then drive for 30 minutes at 2000 revs without braking. I can’t do a forced regen at the mechanic because it might cause a fire, and the car will automatically attempt a regen whenever it thinks it needs to (without telling me, apaprently) so I have to drive like this ALL THE TIME because there is no way to know when the car needs to do a regen. (I don’t get the solid light).
Also, when it’s in automatic, my Subaru only does about 1500 revs, even at 100km/h with constant throttle, so I have to put it in manual to get the revs up. And I can’t use cruise control or brake and I have to do this pretty much all the time and if I don’t, I will need to get my oil changed and the computer reset every 2 months for the life of the car.
Surely, this isn’t normal!
Why is the car trying to do a regen every 90K? (About every 1-2 days) when there is barely any soot or ash to burn off?
Why does the light go straight to flashing? Why doesn’t it tell me when I need to do a regen and then let me decide when it’s safe/appropriate to do one? Why do I never get the solid light before the flashing one?
In short, why is my car gaslighting me???
For now I have an automatic car that I have to drive in manual, adaptive cruise control that I can’t use and a car that wants to drive at 1500revs in automatic when it should be (for its own safety) driving at 2000 revs. Oh, and if I use the brakes I’ll need an oil change every 2 months for the rest of the car’s life. And if I don’t do all this, I’ll need to get a new DPF filter bit even then it’ll still keep happening because I’m still driving it wrong.
So, I have some questions.
1. I have to get the engine ‘hot’? How hot? If I drive at 2500 revs, I can get the engine temp to about half way up. Is that hot enough?
2. Could there be something else going on? A problem with the oil? A problem with the DPF sensor?
3. Have I understood the info I’ve been told? Or am I an idiot crazy person who can’t drive?
The car is second hand so I can’t return it, but it’s got a 12 month statutory warranty because I bought it from a dealer. The dealer is about 100km away and they won’t answer my calls or emails. I don’t want to drive there until I have proof that there’s a fault that they have to repair, otherwise they’ll just say that it’s my fault and I’m driving it wrong.
Does anyone have any suggestions ? Or anything I can try?
I recently bought my first Subaru and my first diesel. It’s a lovely, smooth car to drive and it’s a BEAST, but it turns out it’s also a bit of a princess.
It’s a 2016 Subaru Outback turbo diesel. I bought it second hand and it had only done 40,000 km over 7 years so I thought it was a bargain. After 3 weeks, the DPF light came on. It didn’t go solid, it went straight to flashing. I took it to the subaru mechanic and they said it just needed an oil change. This was when I learned that diesel engines don’t like suburban driving. They like long drives on the highway.
Luckily, I do most of my driving on the highway, which is why I bought the diesel.
Two months and about 5000km later, it happened again. The DPF light went straight to flashing. The oil level was high and apparently the car has been trying to regen but aborting. The mechanic says it’s my fault because I’m not driving it properly. I’m braking too much, not getting the engine hot enough, and not doing long enough trips.
But that doesn’t seem right.
According to my car log book, 78% of my km’s are work trips. This means 30mins of driving at 100k/hour with steady throttle and not breaking unless someone stops suddenly in front of me twice per day.
The stats the mechanic gave me are:
Oil dilution too high - 15%
DPF condition good
Ash 23%
Soot 21%
Regen attempt 503
Completed 171 (averaging out to every 90kms)
The mechanic says that every time the car tries to regen, it puts diesel into the oil to make it hot enough to burn off the diesel particulates and that’s why the oil gets diluted. She says the way to fix it is I have to ‘teach’ the car to regen only every 200km and then make sure that regen attempt doesn’t abort. I have to get the engine hot, by letting it run in the driveway for up to 10 minutes, then drive for 30 minutes at 2000 revs without braking. I can’t do a forced regen at the mechanic because it might cause a fire, and the car will automatically attempt a regen whenever it thinks it needs to (without telling me, apaprently) so I have to drive like this ALL THE TIME because there is no way to know when the car needs to do a regen. (I don’t get the solid light).
Also, when it’s in automatic, my Subaru only does about 1500 revs, even at 100km/h with constant throttle, so I have to put it in manual to get the revs up. And I can’t use cruise control or brake and I have to do this pretty much all the time and if I don’t, I will need to get my oil changed and the computer reset every 2 months for the life of the car.
Surely, this isn’t normal!
Why is the car trying to do a regen every 90K? (About every 1-2 days) when there is barely any soot or ash to burn off?
Why does the light go straight to flashing? Why doesn’t it tell me when I need to do a regen and then let me decide when it’s safe/appropriate to do one? Why do I never get the solid light before the flashing one?
In short, why is my car gaslighting me???
For now I have an automatic car that I have to drive in manual, adaptive cruise control that I can’t use and a car that wants to drive at 1500revs in automatic when it should be (for its own safety) driving at 2000 revs. Oh, and if I use the brakes I’ll need an oil change every 2 months for the rest of the car’s life. And if I don’t do all this, I’ll need to get a new DPF filter bit even then it’ll still keep happening because I’m still driving it wrong.
So, I have some questions.
1. I have to get the engine ‘hot’? How hot? If I drive at 2500 revs, I can get the engine temp to about half way up. Is that hot enough?
2. Could there be something else going on? A problem with the oil? A problem with the DPF sensor?
3. Have I understood the info I’ve been told? Or am I an idiot crazy person who can’t drive?
The car is second hand so I can’t return it, but it’s got a 12 month statutory warranty because I bought it from a dealer. The dealer is about 100km away and they won’t answer my calls or emails. I don’t want to drive there until I have proof that there’s a fault that they have to repair, otherwise they’ll just say that it’s my fault and I’m driving it wrong.
Does anyone have any suggestions ? Or anything I can try?
