e-Boxer GPF issues in more frequent pace

I have already reported Subaru Forester e-Boxer GPF related observations in this blog.

This time I decided that GPF light deservers own fresh blog post since this is already fourth time I have this informative message (as Subaru calls it) displayed within one year. Reason I decided to write a separate blog post, instead of just updating the older post is that this time I managed to drive just little above 300km since previous “informative message”.

Now this starts to be little worrying. If this is going to bug me more and more often. There is so many great characteristics and features with the Forester that I really do not want to start thinking to drive different car but ultimately that would be the final solution. To find car that does not have GPF implemented at all. Maybe some plug-in car would fit better for me. But before going there, I really want to find way to sort issue out and keep this car. Just thinking that we’re on thin line now.

Driving profile

GPF can be a issue for those who drives short distance driving. Short distance driving is relative of course but from the car point of view travel is too short when engine does not warm-up to the normal operating temperature. Specially oil temperature seems to be crucial. And you need to drive fast enough to get GPF regeneration process started.

In my case it seems that I drive way too often few kilometer stops. To the daycare is just few kilometers away from our home. Similarly grocery store is few kilometers away. During COVID era, I rarely need to go to the office but when I need, it is also less than 10 kilometers away. So there is plenty of those short distance places where to go.

However, during free time, I drive longer distances with my family to nature trails and to other hobbies. So it is not only city type of driving what I have. But still it seems that those occasionally long distance driving’s are not enough to handle Forester GPF issues.

GPF during winter

Also colder outside temperatures during winter, combined to short distance driving is a poison for the GPF. As it is seen from the table in older post, summer time was much easier regarding this GPF issue. Now when temperatures have dropped, it seems to be fact that GPF light lit on with much frequent pace.

Solution for that would be then to drive long distance driving more but is that then more sustainable to the environment? I believe the intention of that filter in the first place was to reduce emissions produced by the car. And now it is required to drive more in order to get that filter operate properly? Greetings to the European Union.

GPF forced regen procedure

This time forced regen procedure followed normal cycle. In other words drive over 60 km/h and keep rpm between 2000 – 2500 rounds per minute. It is little difficult to tell when regen exactly starts but oil temperature display should give a hint. Typically oil temperature seems to be over 80 Celsius degrees while during regen procedure it can be somewhere near 93 Celsius degrees. To get procedure fully completed, it should take approx. twenty minutes to complete. Once procedure is completed, GPF symbol goes off on the car dashboard.

How to fix e-Boxer GPF issues

The best way to fix GPF related issues is to adapt driving style and profile to meet required operating temperatures to get regeneration procedure complete often enough. If GPF light lit on regularly, it is a clear sign that traveled distances are just too short. Only way I can think of is that have longer driving at least on weekly basis.

In my case next step is to drive highway weekly. I am not choosing the nearest grocery store but e.g. on Friday’s I will drive 30 km away from home and see if that sorts the issue out. Another solution would be to download RAV4 Hybrid plug-in price list to my computer and start opting features but Forester is too good car with so many features to love. E.g. excellent drive, all-around-visibility, quietness and superb AWD with hill descent control. Not to forget safety features it has.

Update 15.12.2020

I already thought that now this issue is sorted out when I change my driving behavior so that there is at least weekly highway driving. But no, 15th of the December 900 km later since previous GPF warning I had filter light symbol lit again. This time it required longer regen procedure than usual. Earlier 20 minutes of driving was enough to warning light go away. This time it required 40 minutes of driving. So my next hope is that software update will solve the issue. Based on the comments on this blog post and also confirmed by the local service that there is really a update available by Subaru to address GPF related issue.

Please remember also to check full table how often GPF warning comes in my driving scenarios.


  1. After reading about Forester E-Boxer and user experiences with it, for over a year, I decided that I will wait for the new Forester Sport with 1.8L Turbo engine, until it will be available in UE. Maybe it will be. Maybe the smaller engine will have less emissions, the car will not need an electric motor, will have a decent fuel tank, will not need GPF.


    1. I am glad you have found this blog useful! This kind of comment is very welcome. I assume that 1.8 turbo would be a better option but would not hold my breath while waiting it to be arrived in the Europe. My assumption is that next engine option is the upcoming joint venture full electric car with Toyota.

      I am really looking forward to see if my weekly highway driving sorts out GPF issue and I will report the outcome on this blog too. Stay tuned!


    2. I’m pretty sure that engine will never arrive to EU due to CO2 regulations. Furthermore, if it has direct injection, in order to have it homologated in EU it must have GPF.

      If we are lucky, maybe we can see the new Levorg only when Subaru can sell a pure BEV in order to reduce a lot the whole fleet CO2 average.


  2. sorry to hear this mate; just so you know, that warning light has never flashed in my Subaru, so perhaps it is truly a malfunction, rather than short-distance driving?


      1. Try with E98 / E5 fuel … with shortest driving distance not less then 30 km if started cold … step on, accelerate once warmed up – that can be also joy-ride. Assume you will do first 15K / one year service soon, ask dealer for comments. Should not happen so frequently for sure.


      2. Luckily I have access to the highway almost next to my home. Seems that I live too close for everything to engine warmup properly. Interesting to see if highway driving solves the issue. First service coming in January. Now 12 000km in odometer and one year of driving coming soon.


      3. Asked about GPF issue from local dealer, unofficially there is more Subaru vehicles having same issue, even the brand new ones. However, there is recent Subaru software update available for dealers, by latest tests this will fix this issue. So, assume this latest update is also available for dealers in sunny Finland as we both are under Subaru Nordic. Whatsoever, E98 / E5 fuel will help to improve.

        Liked by 1 person

      4. Software update is interesting news! Hopefully that will improve the situation.

        I am little bit sceptic would 98 octane E5 fuel improve the situation or not. Do you think that it would be smaller ethanol component that makes the difference or higher octane of the fuel?


      5. Actually always used high octane and biocomponent free honest car fuel – still available in Estonia. In your case, probably both, smaller ethanol component and higher octane will improve. Software update will fix – at least so dealer told. You never try you never know.


      6. Not sure how it is in Estonia but here E10 fuel means actually maximum ethanol component. If bio obligations are reached otherwise, e.g. selling renewable diesels enough then E10 gasoline can be actually E5 fuel. Even it is sold as E10.


      7. In EU it’s same rules, but as you said – if bio obligations are reached otherwise, some gasoline stations are able to supply biocomponent free fuel as well. Better fuel will naturally improve all the engines.

        Liked by 1 person

  3. The bulletin SB20-90 has been released about the GPF light illuminating frequently. This is due to the software overestimating soot accumulation amount in the GPF system under cold temperature and/or hard acceleration. A fix will be available in January 2021 SSM4 release.

    Liked by 2 people

  4. Same happened to my XV e-boxer 2020 at 4500 km . I called the dealership (Subaru Bulgaria) and they performed a regeneration 2 weeks ago and informed me that Subaru has been recently requesting from dealerships to send info about all cases with early e-boxer gpf issues. This week they called me back to inform me that they now have a confirmation for a software update for my car. Will let you know more after a few days.

    Liked by 1 person

      1. The last 2 weeks after the dealership re-gen I drove mostly on highway, about 1500 km, and the light did not come up again (neither blinked).
        Today I did the software update at the dealership (took about 1,5 hours in total).
        Will update you after some 3-4000 km. (might take a few months as I do no plan on travelling much).

        Liked by 1 person

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