ECU/Stuttering Follow-Ups

[smkscrn]

Update: post ECU-flash -

 

Brought my LGT back into the dealer yesterday for 7500 mile oil change, rotate, etc...(changed to mobil 1 synthetic as well). Also emailed the service manager before I brought the car in and I spoke with him about how my car still studders and has a rough idle, since they did the ECU update. They drove it and tried pulling the "thats just they ways it is" BS on me, but I didnt buy it and pleaded my 30grand car case that shouldnt effin do this, if the AUDI doesnt, why does this? haha. So, the service manager said he has no idea what to do...and invited me to call SOA customer service and complete another complaint about the issue. I DID so, again, and there rep is looking into it again and is contacting the service manager to find out what they may be able to do further. The SOA customer service person said they will be back in touch with me within 24-48 hours.

 

 

I will post with any news....

 

Joe

[intercede007]

If it was just my driving then it wouldn't have gone away after they sent the ECM to NJ to be reflashed. No, there is definitely something else going on. An AP reflash has been known to reslove the problem to a great extent as well.

 

And see that's exactly the kind of response I like to hear.

 

What I want to know is what registers are being changed. Did Subaru retard the throttle tip-in timing in relation to TPS readings so the engine isn't as aggressive under certain circumstances? That would certainly jive with the (albeit limited) observations I have made with respect to producing the problem only under heavy throttle usage and poor (on my part) clutch management.

 

I haven't researched the AP maps online yet, but I have looked at the revision notes for the COBB maps, and while they do explain what was changed, they are generic at best for their descriptions.

 

Almost makes me long for my old Ford EEC-IV and the SCT tuning software

 

I guess what it might just boil down to is that I'm fooling myself a little bit into thinking that it's a clutch problem. My operation of the clutch is a part of the cause and solution but ultimately does not lie at it's root. Proprietary programming and intellectual property rights are a pain.

 

In the meantime, I guess I'll definatly stick to my "Miss Daisy" driving style and anxiously await a fix (and see if any '06 owners come around and tell us it's gone).

 

Thanks again!

Jon

[Peale]

I met with the southwest Subaru district manager and we took my car for a test drive. All he could say is "yes" there is a problem and they are aware of it. They do not have a 100% fix for it, mainly because they have their hands tied and can't change the engine management too much which could affect emission etc. which is strictly controlled.

 

If enough people keep complaining we may have a chance to get Subaru to do something.

 

He did say that techline suggested if there is still a problem, the dealer could run a cylinder compression test. For what reason I do not know. My car is still in the shop and it does not look good... more to come.

 

The dealer has new 2006s with the same hesitation problem on the lot. I find it unethical that they are allowed to sell new cars with a known problem without informing the buyer first. I'm going to find out if the dealer knew about it when they sold me my car.

 

Hang in there,

/t

[kevjam79]

Could this possible be partly caused by the Clutch Dampener Valve (CDV)?

 

Subaru must know how to fix it completely; if they made a statement like the one above. Does that mean we are running to-lean or to-rich in the area the stutter occurs? I really don't think it is to-rich otherwise there would be gobs of unspent hydrocarbons on the pipes.

 

Does anyone have a fuel pressure, fuel/air ratio, or boost gauge installed that has experience the stutter? How do they react when it occurs? This would be a very interesting addition if anyone has this information.

[intercede007]

Could this possible be partly caused by the Clutch Dampener Valve (CDV)?

 

I still have a sneaking suspicion the clutch and or the flywheel is at the bottom of this.

 

I know Ford still tunes their V8 engines to retard timing (like BIG TIME) on throttle tip in and on aggressive throttle application under a load. Saves transmissions, produces smoother power delivery, cuts emissions, and did I mention it saves Ford from having to replace transmissions?

 

Maybe Subaru is "fixing" the problem by tuning the ECU's to retard timing under heavy throttle application because the clutch, for whatever reason, isn't applying a steady pressure or some other such nonsense.

 

And definatly kevjam, I know a few people around here have installed boost guages. I too would like to see what the engine is doing when this is going on. I'm willing to wager that the engine is performing just as it's supposed to.

 

I'm falling back on the belief that the band-aid is the ECU, but the scab is in the driveline

 

EDIT:

 

Again, as anyone heard of non-US market Legacy's exhibiting this behavior?

[SBT]

Again, as anyone heard of non-US market Legacy's exhibiting this behavior?

 

Other than U.S. markets get the 2.0L twin-scoll turbocharger setup. So we're not exactly comparing apples to apples.

 

FWIW - I do believe that Subaru has mis-tuned this engine to attempt to get it as finely close to zero or ultra-low-polluting as possible and this is what's causing the stutter. If that involves pulling timing, or reducing fuel/air delivery in order to achieve this, then I believe that's what they've done. No other Subaru engine, that I've ever owned, and there have been a lot, has ever done this.

 

SBT

[intercede007]

Other than U.S. markets get the 2.0L twin-scoll turbocharger setup. So we're not exactly comparing apples to apples.

 

SBT

 

That's good information. In that case, what in the drivetrain is also differant?

 

If US model cars are the only Legacy's playing the stuttering game, it's worth finding out differances that exist in the geneology to narrow down the cause.

 

I have a feeling Subaru knows exactly what's wrong with the cars, but just like has been pointed out, some regulations regarding emissions et. al. are hampering a proper fix.

 

If tuned cars aren't suffering from the driveablity problems, and since tuners really aren't programming for emissions requierments (most of the time), it might be a safe bet that we've identified the hang up.

 

I do love a good mystery

Jon

[msmith]

For whatever it's worth, I dropped my car off at the dealer this morning for a service and correction of a few warranty issues. I complained about the stuttering problem to the service writer (without letting the cat out of the bag that I already knew what the problem was) and requested to take the service tech who would be working on the car on a short test drive to show him the problem. He said, "sure, no problem" and called the tech over.

 

I drove the car with the tech and showed him the problem... at that point I calmly mentioned to him that I knew that Subaru was aware of the issue and had a fix of some sort. He said, "Yes, we need to send your ECU out for reprogramming... I'll take care of it".

 

Bottom line: The service writers are not the people you want to drop the "knowledge bomb" on... the tech was completely cool about it.

 

We'll see what happens in a few days when I get the car back.

[eles1]

Does anyone have a fuel pressure, fuel/air ratio, or boost gauge installed that has experience the stutter? How do they react when it occurs? This would be a very interesting addition if anyone has this information.

 

DK (DeerKiller) has done extensive datalogging on his car and the stutter clearly shows up on the graphs. I don't remember which parameters he was logging at the time, but if you search on his posts, I'm sure you'll find it.

[BadAndy]

I took my LGT to the dealer on Monday to get the info to send off to SOA about the reflash and to also fix the floor mat hook that broke. The salesman that sold me the car gave a Baja Turbo 5 speed as my loaner and it drove SMOOOOOOOOTTTTHHHHHHHHHHHHHH the whole day. It was freaking blast to drive compared to my LGT! After getting back into my Legacy, the stutter was ever more noticeable than before I was completely amazed how smooth the Baja engine was compared to my Legacy I'm still waiting to hear back from the service department about getting the ECU reflashed though....If they can't fix this stuttering then I might just get a different vehicle because this sucks having a $27K vehicle that runs no where near as smooth as cheaper built/quality vehicles.

[Peale]

I took my LGT to the dealer on Monday to get the info to send off to SOA about the reflash and to also fix the floor mat hook that broke. The salesman that sold me the car gave a Baja Turbo 5 speed as my loaner and it drove SMOOOOOOOOTTTTHHHHHHHHHHHHHH the whole day. It was freaking blast to drive compared to my LGT! After getting back into my Legacy, the stutter was ever more noticeable than before I was completely amazed how smooth the Baja engine was compared to my Legacy I'm still waiting to hear back from the service department about getting the ECU reflashed though....If they can't fix this stuttering then I might just get a different vehicle because this sucks having a $27K vehicle that runs no where near as smooth as cheaper built/quality vehicles.

 

I have talked to both the Subaru district service manager and one of the top senior master Subaru technicians and they both say that the cars were designed to run very lean to meet EPA. Unfortunately a bit too much, since now they can't change it. I asked the tech how to fix it and he suggested a boost controller, so I asked how would Subaru fix it since a boost controller isn't really helping the warranty, and he said they really can't due to EPA regulations.

With that said, anyone with serious hesitation problems after reflash should tell Subaru to test for any other problems with the car. They ran a compression test on my car and it was not very good, so yesterday I stopped by the dealer to look at my car. My beautiful engine was laying on a roller cart in little pieces, so sad... I'll let you know how it turns out later.

 

/t

[mach_six]

I got my car's ECU re-flashed cause of a problem not related to this 2 weeks ago. I don't think they actually sent it back to subaru to reflash it because I don't think I've experience that problem. But after they reflashed my car it feels so damn sluggish feels like I'm driving a regular 2.5L for most of the time. The turbo seems to kick in at a later RPM than it did before above the 4k RPM range. I basically have to mash so I can feel there's still a turbo under my hood. Sigh doesn't seem like the same car I had before.... I just drove it today for 20 miles since it was re-flashed. It's still under 3100 miles since Jan 1, 05. Maybe it's time I changed it's oil too.

[kevjam79]

I have talked to both the Subaru district service manager and one of the top senior master Subaru technicians and they both say that the cars were designed to run very lean to meet EPA. Unfortunately a bit too much, since now they can't change it. I asked the tech how to fix it and he suggested a boost controller, so I asked how would Subaru fix it since a boost controller isn't really helping the warranty, and he said they really can't due to EPA regulations.

With that said, anyone with serious hesitation problems after reflash should tell Subaru to test for any other problems with the car. They ran a compression test on my car and it was not very good, so yesterday I stopped by the dealer to look at my car. My beautiful engine was laying on a roller cart in little pieces, so sad... I'll let you know how it turns out later.

 

/t

 

WOW!! This is not good. Most of our engines might be toast. Can you get what the District Manager and Senior Master Tech said in writing? From the sounds of it everyone would be better off running a Cobb AP or something similar. Did they give you a A/F ratio that the computer is allowing before the stuttering occurs? Has anyone done a before and after A/F comparison with a Cobb AP? If our motors start eating pistons and rings (after the warranty is complete), we will need to put together a class action lawsuit. I CAN NOT believe Subaru would pull this type of CRAP. WOW!!

 

I need to calm down.

[Peale]

WOW!! This is not good. Most of our engines might be toast. Can you get what the District Manager and Senior Master Tech said in writing? From the sounds of it everyone would be better off running a Cobb AP or something similar. Did they give you a A/F ratio that the computer is allowing before the stuttering occurs? Has anyone done a before and after A/F comparison with a Cobb AP? If our motors start eating pistons and rings (after the warranty is complete), we will need to put together a class action lawsuit. I CAN NOT believe Subaru would pull this type of CRAP. WOW!!

 

I need to calm down.

 

I can not make the conclusion that the engine problem I'm having is also one of the causes for my car's stuttering. Just have to wait and see when I get my car back. It would be very interesting if there was no more stuttering. My car is definitevly running more lean than it should.

 

They seem to be very open to me about the hesitation problem and why they are having such a hard time fixing it. I'm not very happy either, it takes the fun out of driving this otherwise great car.

[luckylegacygtwagon]

WOW!! This is not good. Most of our engines might be toast. Can you get what the District Manager and Senior Master Tech said in writing? From the sounds of it everyone would be better off running a Cobb AP or something similar. Did they give you a A/F ratio that the computer is allowing before the stuttering occurs? Has anyone done a before and after A/F comparison with a Cobb AP? If our motors start eating pistons and rings (after the warranty is complete), we will need to put together a class action lawsuit. I CAN NOT believe Subaru would pull this type of CRAP. WOW!!

 

I need to calm down.

 

 

Does the Cobb AP definitively solve the studdering issue?

[TSiWRX]

^ Yes and no.

 

There's at least one LGTer here who reports no hesitation/"stutter/studder" after an AP reflash, and he's already at some 1000+ miles post-flash.

 

However, the vast majority *_of those who reported "stutter/studder"_* pre-reflash have cited a recurrence of the phenomenon after appx. 300 to 500 miles post-reflash (during the immediate period thereafter, of course, they had no problems). Current consensus is that somehow, our ECU manages to re-learn its old bad habits, leading to recurrence of the "stutter/studder" in the majority of cases.

 

[eles1]

Does the Cobb AP definitively solve the studdering issue?

 

It greatly improves the situation, but doesn't get rid of it completely. I haven't tried the v1.15 maps yet, but I doubt they're much different with respect to the stutter.

[intercede007]

It greatly improves the situation, but doesn't get rid of it completely. I haven't tried the v1.15 maps yet, but I doubt they're much different with respect to the stutter.

 

I'm having a hard time believing then that a lean run condition is causing the issue.

 

I've learned to drive around it personally. I'm still holding onto the notion that it's in the driveline. Either way...

 

I had a fantastic day in the sun with my RBP GT Wagon! No stutters and it just ticked over 1,000 miles

[eles1]

I'm having a hard time believing then that a lean run condition is causing the issue.

 

I don't think it has anything to do with a "lean condition". In fact, our cars run notoriously rich from the factory - at least at WOT. Most of us max out the stock O2 sensor on the low side when datalogging.

 

A couple of the tuners that frequent this forum mentioned that they felt it was an open-loop/closed-loop transition issue. Others feel it has more to do with the drive-by-wire settings.

 

I suppose it could be drivetrain lash, but the fact that stage1 and stage2 programming all but alleviate the condition would suggest that it's not.

[legandrex]

My wife's car had the cooling fan stuck on problem and they replaced the ECU to fix it. I don't notice any stutter with it anymore. My car stutters pretty bad in comparison especially when it is humid outside. I almost wish my cooling fan would stay on so I can get a new ECU too. Her car feels much quicker too. Boost builds quicker by my seat o pants meter. Maybe I should trade her cars.

[emlevins]

legendrex - give us an update on the stuttering issue with your wife's car after you get another 500 or 1K miles on it if you get a chance

 

Thanks....

[intercede007]

I suppose it could be drivetrain lash, but the fact that stage1 and stage2 programming all but alleviate the condition would suggest that it's not.

 

I've talked to several people here and on NASIOC who have said the cars relearned the same behavior after a few hundred miles, even with aftermarket ECU flashes.

 

One dude here said an SOA "rep" stated it was a lean condition they programmed to meet the ULEV code (can't remember exactly..it's on the previous page and I'm lazy ).

 

My dog said it was the beans I ate for lunch....

 

Ugh..shalt their be any continuity?

 

 

*SIGH* Maybe our cars are haunted

[emlevins]

I've talked to several people here and on NASIOC who have said the cars relearned the same behavior after a few hundred miles, even with aftermarket ECU flashes.

 

 

Exactly - which is why folks need to periodically post what happens to the stutter after 500, 1K miles etc. Frequently, after a reflash, the stutter disappears...but then reappears later on. Not sure if that will occur with a new ECU.

[legandrex]

I think my wife's car has more than 500 miles on it since the ecu was replaced. It was over a month ago I believe. So far so good. I will keep you all updated as the miles progress. My car however drove significantly better today with our 30 degree temperature drop (40's this morning). With cool dry air I rarely notice any stutter with my car. Who knows...maybe it is gas related. My wife typically puts Mobil Super in 93 octane and I typically put Sinclair or Phillips (93 octane). Maybe Mobil is a better fuel?

[emosound]

Add me to the list of drivers who are not happy with SOA's "fix".

I have about 1000 miles on my reprogrammed ECU, and while the stutter is reduced, it is still there quite often. Most of my commute is stop-and-go traffic lights, so it gets pretty damn annoying. No modern car should do this, let alone one costing $30k.

Who can we talk to at SOA about this?

I'm going to try to talk to my local dealer's SM about it, see who she can talk to.

 

-Paul