engine stalling

I've long had the stuttering issue, had the ECU reflashed, etc. Over the summer and early fall, I had a handful of times where the engine would stall while approaching a stop sign with the clutch fully engaged, and even transmission in neutral once, but I figured it was a fluke.

 

Over the past month or so, with the colder weather here in New England, the stalling seems to be on the rise. Yesterday and today it stalled 3 times in similar circumstances: I'm going about 30mph in 3rd or 4th, light throttle, approaching stop sign or red light I engage the clutch and get off the throttle. The RPMs drop below the idle level, status lights flicker, and the engine stalls while I am still moving about 20mph. I then lose all power brakes and steering, which can be a bit alarming when you are not expecting it. In at least a few other instances, the indicated RPMs briefly drop to near 0, status lights come on, and it some how recovers on its own. I have had this happen when the coolant temperature was near or at normal temperatures, but it appears more frequent when it is half or below.

 

Has anyone else seen this?

 

I am considering this to be a real safety issue because it is stalling while I am still moving. I've driven manual transmissions for 24 years; I am not late in engaging the clutch. This is the engine having trouble transitioning from driving to idle. Given how badly the ECU is handling the onset of boost in light/moderate acceleration in the 2500-3000 band (stuttering), I really feel like this car has some engine problem. I am really learning to hate throttle by wire.

 

I am about to call the dealer to have them investigate the stalling issue. Since it is a fairly rare event (maybe a once or a few times a week), I seriously doubt I could demonstrate it or they would experience on their own short drive. Should I demand a full engine examination, including checking compression, variable valve timing, fuel delivery, etc.? If they just give it a short drive and try to pull codes, I expect they will find nothing, and that doesn't help me.

 

I'm really beginning to wonder if my first foray into Subarus was a mistake. My 10-year old VW Golf was more reliable: no stutters, no stalls. However, it certainly wasn't as much fun. Still, being less reliable than a Mexico-built VW isn't a good sign. I'd really like to get to the bottom of my engine/ECU issues. What will it take to make Subaru pay attention?

 

--Lee

Your problem doesn't sound like an ECU issue...sounds more like a sticking or faulty OCV valve...

 

maybe the shop you are taking it to is looking in the wrong area...

 

what type/weight oil are you using?

Thanks. Would I expect a CEL or for them to find codes related to a sticky or fault OCV? I have never had a CEL.

 

The dealer put in Castrol Syntec less than a month ago. I confess I don't know what weight they put in.

 

--Lee

It can trigger a CEL if the actual solenoid fails, but if it sticks for just a second it won't...and that quick stick could be enough to stall the car...

 

If they put a "heavy" oil in it can contribute to the sticking, synthetic or not. I would recomend sticking to either a 5W30 or a 10W30 if you are in a hot enviroment.

Thanks again.

 

BTW, it has Syntec 5W30.

 

--Lee

I just got back from the dealer. A tech took it out with a computer logging things. Apparently the O2 sensor output was stuck at 1% (or so they say), so they are ordering a new O2 sensor. I asked why no CEL, and they have no clue, and say the "computer" checks out OK. Does that make sense?

 

They have to order an O2 sensor, which will take 2-3 days to come. How come a dealer doesn't bother to stock an O2 sensor for a current model, even in the whole Boston area? Nice one Subaru. When I asked why they didn't stock any, they said they've never had a new one fail. Just my luck.

 

Oh, they found a pin hole leak in the oil filter they installed a few weeks ago. I guess they didn't get the memo telling them to stop installing that bad batch. Even I knew about that from here. Another nice one Subaru.

 

Next Monday I get a new O2 sensor. I'm wondering if it will make a difference or if it is the ECU itself misreading it. I'm wondering if this will help my turbo surging/stuttering, which isn't too bad recently in the colder weather.

 

--Lee

i have the same problem w my 5eat coming to a stop it will stall in gear or it will catch its self. ive taken it to the tuner and he just installed a oil catch can sayin to much oil blowby in the intake and it cant burn it but it just stalled again.. i dont know what to do no cel i have turbo back exhaust spt intake and stage 2 cobb.. we messed the the idle when coming to a stop i would idle up 3% but it was to much so went to 1% and it stalled again... this sucks soooooooo bad

I ran into the same 'stall' problem with my 2006 Legacy Spec B. Six months ago, the engine stalled for the first time -- roughly 90 seconds after I started it in the morning, as I began to slow down for traffic. I thought this was an anomaly, but the problem has been getting worse.

 

> The engine stalls approximately 60 seconds after I start the Legacy in the morning, to head to work.

 

> The engine stalls ONLY when I lift my foot off the accelerator, e.g. approaching a stop light or stopped traffic.

 

> The 'check engine' light comes on.

 

> This occurs only in the morning -- after the first time the Legacy is started. When I restart it later in the same day, no problem.

 

> The problem has been getting worse. Now it stalls 2 or 3 times in succession in the morning.

 

> After the first trip to the Subaru dealer, they blamed the problem on "bad gas", and said no events were recorded on the computer. (They also flashed the EPROM / ECU, however -- indicating that they thought there might be another problem.)

 

> The second trip to the dealer is scheduled next week. I will let you and the Forum know what they found.

Hi. we're having the same problem. Anyone find a solution?

 

Thank you!

My problem ended up being a sticky electronic throttle body. Apparently it would stick in the closed position, and when the ECU would command it to open a bit to raise idle it wouldn't react. This was fixed spring 2006 and hasn't recurred since. I know my dealer and New England service rep took quite a while to diagnose this, partly because it didn't happen reliably. I know they did a bunch of data logging at the time.

I have this problem when car stalls when switching from warm up cycle for about a year. But now all of sudden car stalls all the time until engine warms up. I tried data logging but that did not reveal much. Just that RPM drops right before the stall.

 

Would love to try replacing throttle body but the part alone is $450.

 

Has anybody else solve their cold stalls? I would like to know that there are more cases of bad throttle body before dropping cash on it.

weird