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-   -   Low rough idle and stalling (http://legacygt.com/forums/showthread.php?t=183903)

Pondrat 04-14-2012 07:17 PM

Low rough idle and stalling
 
http://img.tapatalk.com/c6e4c11f-2124-243f.jpgIt seems like randomly my 2005 5EAT with 16g BNR has been having a low idle. It has stalled 3 times at slow speeds. All three seem to be when it's warmed up. No CELs, computer says no pending codes. Vacuum hose to BOV attached. Gas is good gas from Shell 93 always. Of note, it started happening after an oil change that my mechanic did. Here's a pic of idle in drive while stopped at a light.

Any ideas? Mechanic mentioned sounds like 2 other occasions he's run into when the air fuel sensor was bad. Specifically the part about not throwing codes. He said wait until it gets worse to declare itself. Help!

SWP XT 04-14-2012 07:42 PM

You checked the hose where it goes into the manifold under the TMIC? This is also a common disconnect point. Extended driving would likely generate a Bank 1 too lean code though.

Does it behave the same way in Nuetral (I see you have 5EAT) as it does when in Drive at a stop?

Pondrat 04-15-2012 07:40 AM

Haven't checked under the TMIC for hose and haven't tried in neutral but good ideas. I'll do that and report back.

Anyone want to buy a 2005 GT wagon with 91k miles? I swear it has no issues whatsoever...

Max Capacity 04-15-2012 04:44 PM

Clean the MAF and if that doesn't help. think about replacing the o-rings under the intake manifold.

SWP XT 04-21-2012 06:07 AM

Update? What did you discover this week?

20lgt06 04-21-2012 06:14 AM

if you replaced the turbo i am assuming the turbo inlet is ripped.. BOOST leak test

Pondrat 04-21-2012 05:33 PM

Update - idle is not so bad in neutral, but I think that makes sense as its not under any load. Vacuum hoses under TMIC are all set.

It hasn't stalled or felt like it was about to since I wrote the original post. Therapeutic forum posting perhaps? Or maybe the ECU learned a thing or two since then. Either way, I'm going to wait for it to get worse or start happening again before I touch anything else in fear of making a little problem a big one.

Thanks to all those who offered their time and ideas. I love this place!

Seriously, anyone want to buy an awesome mom-mobile? No known issues...no CEL - the truth!

Pondrat 04-21-2012 05:35 PM

Oh, and yes, the turbo inlet tube was ripped. By the mechanic who installed the new turbo who graciously replaced it with a new one at his cost. So I assume it's still good.

20lgt06 04-22-2012 12:14 PM

i am in the same boat as you- stage 3- had the heads rebuilt car runs like yours- stalls idle is rough. went away after driving 2-300 miles but rpms dips every so often, then replaced my turbo inlet because the mechanic ripped it reset my ecu and now its bad --- well see when it relearns.

hadvw 04-22-2012 07:19 PM

This is EXACTLY the problem I'm trying to diagnose on my 5EAT bnr16g wagon with 85k miles - almost exactly like your car. Have had the evo16g for about 23k miles now. Did it a few times last year, but much more pronounced this year.

For me, it does NOT happen when cold, due to extra fuel/idle boost when cold. Also, when fully warmed up, does NOT happen. Only, when it gets past the 1/6 temp hash mark and is not fully warmed up yet (here, in NorCal, from about 3-4 minutes after startup to about 7-8 minutes after startup).

I have found that dropping to neutral and revving past 4k rpm one time seems to mostly solve the issue, although that's probably not great for a not fully warmed up car yet.

No idea what the problem is - I've briefly checked vac hoses and found nothing. Haven't had much time lately to work on the car - super busy at work and at home. Car still seems to run fine under WOT.

I do have 650cc injectors (deatschwerks) + walbro. I figure it can't be failing fuel pump, because it's fine when cold and fine when warm. Probably not vac hoses either, since then it would also do this when hot - but when hot, idle is mostly stable, although sometimes lumpy, but never stalls.

Sometimes, after driving a while, get a "burnt" smell - not sure if it's oil, or the CV boot is dripping onto the DP again..

I have thought that maybe the injectors are clogged a little, or aren't calibrated too well?

I have an AP 1 tune. Is there any simple "bump idle" adjustment on these cars in the tune? I'd be just fine with a higher-than-normal idle if it stops this problem. Have not had time to check my turbo inlet - that's next. Had a similar problem with my first car - '84 GLI - and that was a cracked intake pipe, and this is acting similarly. Solution on the GLI was to adjust the idle stop setting - wish there was something like that on this car :-)

Anyway, would love to try to work together to try to solve this - it's the one major dislike I have of this car right now..

Could it be headgaskets? When my in-law's 2.0l 16v GTI had the headgasket go, it would still drive under WOT, but would stall at idle (and I think the same for their Saturn DOHC wagon). I've also thought about a cracked ringland? Possible?

If you search, you'll see a few of my posts with the same symptoms, and no real solutions/advice. Pretty much stumped at this point.

Does Cobb make their AP v1 protuner software available? I have an unlocked tune, so I could mess around with it to see if I could fix this...

Pondrat 04-23-2012 01:12 PM

Hadvw you're description of the problem is like you read my mind. My head gasket was replaced very recently so I HOPE its not that.

I also get a burnt smell. I had a massive oil leak from a faulty oil filter last year and there was a ton of oil under the car for a long. Maybe even still. Also my inner CV boots were a little torn and recently replaced. I had thought the smells of burning from both instances had gone away and maybe they did ,maybe they didn't but it's definitely back now. Weird that you're having it as well.

Please PM me if you find resolution. I'll do the same.

bmx045 04-23-2012 01:51 PM

I'm going to assume you got my Pm.

hadvw 04-23-2012 02:04 PM

Quote:

Originally Posted by Pondrat (Post 3860894)
Please PM me if you find resolution. I'll do the same.

Sure.. But let's keep this thread for brainstorming, and see if anyone else can chime in..

I believe a compression test would reveal head gasket problems, but I've heard not necessarily ring lands.

Best way to test for vacuum leaks? Still seeing 21 psi on my gtdigboost20 when I floor it in 4th/5th (connected after TMIC).

Wish I had more time to spend on this..

bmx045 04-23-2012 02:09 PM

compression test confirms or disproves the sealing properties of the pistons and of the valves, yes a leaking head gasket can cause low compression but is certainly not a likely scenario in these cars as our HG's are metal.

find someone or make a boost leak tester, it's been discussed on this forum plenty. charge the intake inlet pipe with air and listen for hissing. when my intake manifold gaskets were bad it would stumble and almost stall due to an unmetered air leak, but so did when i had low compression in 2 cylinders....

hadvw 04-24-2012 10:01 AM

Quote:

Originally Posted by bmx045 (Post 3861014)
compression test confirms or disproves the sealing properties of the pistons and of the valves, yes a leaking head gasket can cause low compression but is certainly not a likely scenario in these cars as our HG's are metal.

find someone or make a boost leak tester, it's been discussed on this forum plenty. charge the intake inlet pipe with air and listen for hissing. when my intake manifold gaskets were bad it would stumble and almost stall due to an unmetered air leak, but so did when i had low compression in 2 cylinders....

Thanks.. Will try to find some time to do this.. Would love to know the problem..


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