2010 Diesel Drivetrain shudder

[pitrack_1]

MY11OBD,

Economy:
~6.6l/100km around town
~7-7.2l/100km highway.

We get ~800km before refilling (at the yellow light, still 10-15l left)

Note I drive around town like your old grandma with a governor fitted to an 1100cc Beetle and mostly outside peak hour. On the highway, I sit on a GPS 110km/h, 2 people on board + minimal luggage.

Shifting:
Please see my other post regarding the Subaru Aust diesel shifting point advice for my rpms against speeds. Also note my speedo vs GPS calibration.

5th at 100:
The shudder you describe in 5th at 100km/h I haven't had since very early on, and worries me a bit. I have felt a very slight 'notch' in performance sometimes around 100km/h in 5th, I think the regen may happen then. I have also caught what feels like the turbo 'off boost' around 60-70 km/h when I want to accelerate. In both cases I have found the solution is to smoothly press the accelerator to the floor and hold it there. It seems to send a 'wake up' to the ECM to 'do something, now' and it will respond in a second or two. The only other thing I could suggest is change fuel suppliers and see if that makes a difference. I tend to use Shell, sometimes Woolies, governed by dockets of course.

I can also say that (all speedo speeds below)
- 60 in 4th is too low for me
- 80 in 5th is too low for me
- 100 in 6th is too low for me (below 2000rpm)
for comfortable driving- the engine is starting to labour.

Speedo speeds such as 60, 80, 100 find me caught 'between gears'. Using GPS speeds allows me to use the higher gear comfortably. And I don't get booked- that many cops-in-the-bushes on the Syd-Canberra run over many years can't be wrong (or asleep)!

Strange happening: I actually went past a radar tonight whilst sitting on a gps-60km/h on a known speeding zone doing my tests. I saw the guy pointing the radar at me, then put it down. It's about the only time I've actually seen someone point the radar/lidar at me. I'm sure the car that had raced up my cl*cker over the past few 100 metres was happy (s)he didn't zoom past me or been ahead of me at that point. The car? An early WRX!

Stranger happening: On the way back, another vehicle from NSW came past me. He turned up my roads on my way home. The cop had finished with someone ahead of us, turned off his lights and pulled out between me and the car in front, and sped up to follow it. He then proceeded to pull the car over for either some minor infringement, a breath test, or because the car was a 'cop magnet'. The 'cop magnet'? A Legacy (not Liberty) turbo wagon, lowered, with NSW plates in the ACT...

WEIRD coincidences!

G'Day Pitrack 1, you words are very interesting and encouraging.
Since I had my DPF regen done at around 4,500km I am now up to almost 10,000km without the DPF light comming back on. However during this time have ensured revs remained high when changing gears.

I am now driving mostly 4th at 80km above and 5th on 100km. found that shudder occurs at 5th on 100km around 2000 rpm, yet putting in 6th at 100km its at 1800 rpm. For me the shudder occurs more when changing to 5th going up to 100km at 2000 rpm.

With the shifting style you have shown, what is the rpm's? what is your average consumption over 1 tank?

[MY11OBD]

Pitrack_1 your values for fuel should be other way round right?

I am getting around the 6.8 combined FWY and town driving. Depending on traffic it could be start stop on FWN leg going to and from work.

It seems driving style like the way you've mentioned will remove the DPF light from appearing as since I have taken on a more harsh approach to driving the Diesel, the DPF light has never reappeard.

I am thinking your thoughts on turbo loss or regeneration is happening when we get this so called Shudder.

Your GPS speeds are almost spot on with mine, i am using a Navman and typcially will use it on long country trips. Around town I'd stick to the speedo as indicated so I stay clear of the police.

I am putting the car in for service end of this month and have reported this on the booking. Lets see what advise I get from the techs or if any at all.

Has anyone heard more from what is happening at FHI?

the shudder is occuring once each day as I drive back from work to home. Early in the morning to work shudder has never happened.

[pitrack_1]

MY11OBD,

No my values are the correct way around! I seem to be more efficient in the 'city'. I drive like a Sunday grandpa around town (watch for that hat!) but keep the revs up a bit. My other cars- SP23 and N13 Pulsar- show similar results; city/country similar or only marginally favour country.

Just did 6.8l/100km from trip computer after solely 'country' (freeway) running back to Canberra- country maybe a bit better than quoted previously.

Just occasionally on the trip I could feel the slightest glitch / shudder / loss of power/response around 2000-2200rpm- I think regen. Fuel use also went up eg from 8l/100km to 9l/100km. Issues disappeared after a second or two if I planted my foot.

It does sound like you and others are having a harder time / bigger problem than me, however.

A thought- the continuous shudder may be a hysteresis effect- "yes you can, no you can't" swapover argument in the CPU. Just as the regen hits the value to kick in, it's also at the value to kick out giving a continuous swapover shudder. Perhaps try changing your speed/gear/throttle position a bit. Does it happen on cruise at a particular speed/gear? Even a particular stretch of road?

Some interesting info elsewhere (subaruforester.org I think) on what happens during a regen- fuel injection, turbo geometry, even apparently airflow restriction during regen.

The Liberty/outback share this diesel engine, but the Forester has a different exhaust system which changes the outputs slightly (I think we're down 1 or 2 kW c.f. Outback). Haven't heard too many outback complaints, so I wonder if this also could be contributory.

Another idea from left field- I wonder if this shudder is, by any chance, actually a compressor stall in the turbo? Bit like a SR-71 'unstart', just less severe...

The combined opinions of an ex Toyota dealer mechanic, a Subaru dealership, an ex fuel refinery scientist and a current diesel mechanic I've spoken to are that Australia's fuels aren't much chop compared to Europe/ North America. Quite variable and subject to contamination. So perhaps try changing your refuelling supplier also.

The diesel mechanic services Isuzu trucks where the first thing he does is initiate a DPF burn following instructions listed in the handbook. These run automatically at ~1100-1500rpm for 10-15 mins. These engines redline is 2800rpm, ours ~4750rpm, so multiplying 1100 - 1500 by the ratio 4750/2800 gives 1865- 2544rpm...very close to our listed DPF burn range.

"Special' tool, indeed...so where's our instructions, Subaru? Hmmmm????

[MY11OBD]

I tried your suggestion to vary the throttle and this seems to have some affect. the accelerator is depressed more when i feel shudder occurs i will give this more testing. maybe engine sense this.

very interesting your values are that way. i am getting more economy FW and HWY mixed with town drivng.

[drwormy]

I originally was in the market for the Outback Diesel and did a~ 30 km test drive of it. Fuel economy on the fwy doing 110-120 (by the speedo) hovered around 5.6 - 6 L/100 km. Thats a bit more than the fuel economy i get from my forester going ~ 80 km/hr in 5th. Push the speed up to 110 in the Foz and i get closer to 6.8-7. As someone else has pointed out the aerodynamics of the Foz arent that great - a brick with ears (if it had ears), so my conclusion is the Outback might be more fuel efficient on the hwy. This is certainly my anecdotal experience with my old MY06 outback and friends foresters.

very interesting your values are that way. i am getting more economy FW and HWY mixed with town drivng.

[Doubtback]

In the meantine, I think your best bet is to take a printout of this thread to your service departments as a document to prove that there is a growing number of Diesel owners with the same problem. I indicated to my service department that there is a new shudder victim joining the forum roughly every week. I am guessing for every one person on this forum with the shudder, there is probably 3 to 4 more who havent posted.

Well today I took the vehicle in for it's 25,000k service and took a copy of this thread(BIG mistake - anyone else tried it ?).I might as well as taken the daily newspaper as I was told 'Subaru does NOT take notice of anything mentioned on forums'. I told them Subaru was not suporting me and the only support I was getting on this issue was on these forums. I was told ONCE AGAIN that it is a DPF issue causing the shudder. I mentioned that the Subaru Technical team should be aware of the shudder problem as Skipalami has been telling us - but seems like they don't ! They were a bit disbelieving that a Service Centre would also not want to say who they are if they are trying to help a customer. So suffice to say I came away unhappy. I persisted with my questioning and mentioned that even IF it was was a DPF issue then the was the car behaves is totally unacceptable. The guy at the service desk said he would try and make further enquiries and call me in a couple of days. I think he might have got an earful from the Subaru Techincal team as he said he felt like the meat in the sandwich. He said the only way they can look at the problem is to experience it first hand which as I've said before I cannot make this happen at will.

[Subyroo]

Well today I took the vehicle in for it's 25,000k service and took a copy of this thread(BIG mistake - anyone else tried it ?).I might as well as taken the daily newspaper as I was told 'Subaru does NOT take notice of anything mentioned on forums'. I told them Subaru was not suporting me and the only support I was getting on this issue was on these forums. I was told ONCE AGAIN that it is a DPF issue causing the shudder. I mentioned that the Subaru Technical team should be aware of the shudder problem as Skipalami has been telling us - but seems like they don't ! They were a bit disbelieving that a Service Centre would also not want to say who they are if they are trying to help a customer. So suffice to say I came away unhappy. I persisted with my questioning and mentioned that even IF it was was a DPF issue then the was the car behaves is totally unacceptable. The guy at the service desk said he would try and make further enquiries and call me in a couple of days. I think he might have got an earful from the Subaru Techincal team as he said he felt like the meat in the sandwich. He said the only way they can look at the problem is to experience it first hand which as I've said before I cannot make this happen at will.

Your dealership not doing you - the Subaru Diesel or Subaru themselves any favors by denying the problem.

Seems to me that the only place suitable for a Diesel Forester is the Nullabor - dead flat.



The amount of workshops that discount internet Forums as bunkum are unbelievable, it's as if they think the Forum will take over their business and run them out of town. Where else will they get free testers trying to recreate or solve problem/s for them?, the least they could do is at least have read of the complaints and suggested causes.

I can see myself going back to riding a horse shortly, only Gillard's carbon tax will tax it off the road too.

[ForesterDiesel]

I'm worried.

Do I, or don't I, buy a diesel Forrester?

Daily drive a 70km trip to work and back, mostly 80 or 100kph. And yes, hills.

[pitrack_1]

I have a contact whose Forester is going in to his dealer tomorrow for this shudder problem, which was chronic. Passengers were NOT pleased, and he had to answer to his family too! He has been told it is the EGR valve to be replaced. This, of course, does relate to emission control and affects the DPF- from what I read elsewhere.

He is to do a trip down to Canberra (to see me) and then beyond (from Sydney) on Wed/Thurs next week. So I'll let you know what happens. This may be something to watch out for. Heard about problems with EGR elsewhere too.

Drwormy: yes I agree the fuel economy blows out quickly above ~80km/h.

Doubtback: Since at least they Leyland days, a new car should not shudder uncontrollably under normal driving conditions after less than 12 months and 25,000kms. "Fit for the purpose for which it was sold" is the term. The dealer as Subaru's representative has a legal obligation to help you under warranty (and perhaps even if not), and you have a legal right to have the problem fixed. Perhaps don't tell them exactly what the cause is, just quietly say there's a problem, this is what happens, under what conditions, it's not good enough- find it and fix it. Keeping an occurrence log helps. And they should supply a suitable courtesy vehicle in the meantime. Invite the Dealer principal/MD to swap cars with you. Point to a shiny new car-of-your-choice and say "I'll take that in the meantime." (Might work). Otherwise, find a better dealer- there are some around. I drive from Canberra to Sydney to get good service for certain things.

I have found a dealer good for sales is not necessarily good for service, and vice versa.

Subyroo: Given the response/service some are receiving, some dealers should be run out of town- perhaps you could round up a posse on your horse! And sorry but it's a good thing the carbon tax will penalise your horse: methane is much worse than CO2 as a greenhouse gas. Besides, I don't like manure up the side of my shiny new Forester

[Falco80]

Hello guys,

First post here. This is my first Subaru, but not my first diesel. I came across this topic while searching for DPF info, as the DPF light came on flashing twice today for the first time.

I bought my Forester in January and today it rolled over 8800km's. I drive on average 1000km's a week and have always driven it with the DPF in mind. I hate the idea of the DPF straight up, and was a bit hesitant buying a turbo diesel that has one, but everything else about the Forester made it hard to pass up.

I never lug this engine around under 2000rpm's, or accelerate hard when it is spinning under 2000rpm. Since i'm on the highway most the time i am always alternating between 4th, 5th and 6th just to mix the revs up and get it on full boost regularly. When the light came on today it surprised me. There's no way my DPF could be getting blocked!

I have also noticed sometimes as well, that when i'm driving it a bit hard the engine seems to be caught off boost in between gears, even though it's doing around 2500rpm. It hesitates to accelerate for a second or two even though my right foot is against the firewall. I have not experienced the "shudder" as yet.

I rang my service centre this arvo and they've made a note of it for when i head in for the 6m/12.5k service next week. I'm going to ring back tomorrow and try to talk to one of the mechanics there, or the supervisor, just to see what there opinion is.

I'm hoping this is not a big issue, as i love the vehicle and i love the little boxer diesel...so far.

Cheers,
Dan

[skipalami]

Doubtback,

I am really sorry you got shafted by your service centre. It sounds to me like they are just plain lazy. I also apologise that they seemed to write you off since my service centre doesn't want to be made public yet. My service centre has placed a great deal of trust in me and I can't betray that. I do feel a bit responsible, so I am sorry in that regard.

I find it interesting that your service department claim Subaru Technical have no idea of the problem. Perhaps they called the fish and chip shop accidentally?? I know for a fact that Technical know about it.

The other way to look at it is Subaru Aust. may have instructed service centres to blame the DPF until further notice so as not to cause a stampede of customers wanting a fix. We all know that the DPF reason washes a couple of times until eventually you reach the realisation that there must be something more sinister going on. I personally think the DPF is involved, however it is not the root cause.

Just savor the moment when they have to pucker up and fix your car when the eventual fix is released.

BTW, Obviously my advice to take a copy of the thread to your service department is dumb, so be warned. Ironically, my service actually wanted to have a read.

[Subyroo]

Subyroo: Given the response/service some are receiving, some dealers should be run out of town- perhaps you could round up a posse on your horse!

Happy to oblige mate!

And sorry but it's a good thing the carbon tax will penalise your horse: methane is much worse than CO2 as a greenhouse gas.

The bloody tablets I take make me produce more methane than a mob of horses, so it looks like I'm on the endangered list too.

Besides, I don't like manure up the side of my shiny new Forester

It sounds like it is alive and well and living under your bonnet at the moment.
P.S. Couldn't help myself there.

I honestly hope that Subaru solve everybodies problem and quickly too.

[skipalami]

Hello guys,

I have not experienced the "shudder" as yet.

Falco80,

I really hope you never experience the shudder, however I will say this.

It will be like getting your privates caught in the car door...i.e.It will be tough not to notice.

[Ricker]

Hi there,
I have noticed that my car attempts regens very regularly. At least once every two days until it gets a decent run and finish's up. Then it'll stay good for a week or two and start doing them again. Admittedly i'm doing 8km trips to work each day which takes no longer than 7-8 minutes.

I dont care too much, as majority of the time it takes the car about 5-6 minutes to work out it can start doing its regen again, and by that time I've had a fair bit of fun in the car with its torque and i'm at work already

What I have noticed on a longer run when the car was doing a regen. I was stopped at the lights for a good 5 minutes, and when I pulled off in first and gave it some, a massive exhaust plume of black smoke left my tailpipe and smoked out the car behind.

I've had this happen about twice now when stopped at lights, and once when I started my car in the garage?

Any ideas on whats causing this?
I'm also not certain as to whether i've experienced this so called "shudder" or not. Sure i've noticed the cars not to happy running down at 1800 or lower but nothing thats ever shaked me in the seat.

I've never driven the car and made the shifts as the owners manual stated. I always found that they were shifting far to early, and the car was hugely labouring to maintain the load. I always shift somewhere around the 3-4k mark between 1-2 and around the 2.6-3k mark for 3-4th. I hit up 5th gear when at 90 and switch to 6th when i'm at about 110.

I like enjoying the torque the car provides and aint bothered by higher fuel consumption like 8L/100 around town.

[pitrack_1]

Ricker and Falco80: I have experienced the shudder once. I shudder at the thought of it...(sorry! )

Best approximation to the shudder I can think of is thus:
- Place an unbalanced load in your top-loading washing machine.
- Close the lid and sit on it.
- Start the spin cycle.

Bonus points if you also subject each of your passengers to the above.

The only benefit to doing it in a Subaru is that, unlike the top-loader, it can subject all of you to the shudder simultaneously whilst safely strapped in- thereby saving you time and possible lawsuits.

[pitrack_1]

The following are a couple of articles I found in the Internet that relate to DPF regeneration and oil dilution. May also be of interest to Falco80 in the "Diesel Particulate Filter - DPF " thread as that is what he experienced.

It would also be interesting to know if the Subaru ECU actually measures the oil dilution or only estimates it based on the number of regens done.

Firstly, basic background info on Wikipedia

http://en.wikipedia.org/wiki/Diesel_particulate_filter


The following explains some oil dilution issues. I assume we have the retarded post-injection/ exhaust stroke in-cylinder injection, this is probably borne out by Falco80's experience- otherwise he's got more issues to come! It is interesting how the problem is becoming worse with newer vehicles, and in a way, a repeat of petrol vehicle oil dilution from stuck/improperly used chokes or malfunctioning/maladjusted carbies in the 'olden days'.

http://www.1st-in-synthetics.com/articl ... ngines.htm


And here is a uni-related article on actually testing oil dilution from DPF regen exhaust stroke in-cylinder injection. Those considering biodiesel may do well to read it. It concentrates on B10 blend (10%) biodiesel but you can interpret the info back to straight fossil diesel. I believe this is the VW diesel engine (103kW version and VW do sponsor this report!) and the dilution results for differing engine performance levels/uses are certainly interesting.

http://www.ufop.de/downloads/Kurzfassun ... l_0709.pdf

[Subyroo]

Best approximation to the shudder I can think of is thus:
- Place an unbalanced load in your top-loading washing machine.
- Close the lid and sit on it.
- Start the spin cycle.

The only people who do that are frustrated old spinsters.

[pitrack_1]

I have a contact whose Forester is going in to his dealer tomorrow for this shudder problem, which was chronic. Passengers were NOT pleased, and he had to answer to his family too! He has been told it is the EGR valve to be replaced. This, of course, does relate to emission control and affects the DPF- from what I read elsewhere.

He is to do a trip down to Canberra (to see me) and then beyond (from Sydney) on Wed/Thurs next week. So I'll let you know what happens. This may be something to watch out for. Heard about problems with EGR elsewhere too.

Well my mate had his EGR valve replaced on Friday- and apparently they put in a slightly different one. Either Subaru are buying whichever off-the-shelf EGR valves are available or they've implemented a change.

However, it has not solved the problem. Shudder continues, manifested itself on the freeway yesterday at 90km/h in 6th, then 5th, then 4th as well! Back to the drawing board... and the dealer.

Unaffected, I am truly one of the lucky ones...so far.

The only people who do that are frustrated old spinsters.

Better stop, we're going around in circles...

[subdiesel]

It would also be interesting to know if the Subaru ECU actually measures the oil dilution or only estimates it based on the number of regens done.

It cannot. Generally the car does not have super special sensors that could measure oil dilution, fuel quality, fuel energy etc.
AFAIK newest models have a simple oil level (warning) switch, won't help much with detecting dilution amount I guess.
Same with fuel consumption, you'd need expensive (lab) equipment in order to measure such properties accurately.
Instead, the ECU software takes (educated) guesses, uses counters, calculates estimations.
The engine does have standard sensors of course, all the usual suspects like temperatures, pressures, mass air flow...
Most of the sensors are digitized by the ECU itself. Some are directly connected to warning lights (oil pressure, brake fluid level, ...) only - ECU does not know about these.
I think I know where the oil dilution calc algorithm lives, it can increase or decrease the value. Sorry to say haven't got the time to dig in.

[GTlegs]

So, can you guys please confirm that this issue relates to manual diesel cars only?

I am looking at a petrol 4 cyl CVT car at the moment and want to tmake sure it does not have this issue.