Strange low Idle and Stalling at times

Hey guys,

Im starting this thread just in-case it gets more involved. Driving the vehicle home last night, got stuck in some traffic.. I was just rolling in traffic, when vehicle exhaust note would change, idle would drop, and if I didn't save it in time or put it in Neutral the car would stall. It would then start right back up no problem in either N or P. Same thing this morning on the way to work. And on top of that vehicle is acting funny on first accel, seems like delayed throttle response

Background- Tuesday had vacuum leak on intake, fixed as far as I can Tell. Tuesday also removed battery to get to HID ballast that went bad. Wensday- removed battery again to replace bad HID ballast, also had to replace negative battery cable end.

My thoughts- I need to reset ecu with Cobb, I figured battery out for awhile would have done it, at this point I don't think it did.. Is there an idle reset on these things I can do with a cobb or Gensis? Need to check for more intake leaks, I have a feeling the TMIC is giving up the ghost, but theres no noise that is typically described when they start to go..

I've never logged or anything, so if you guys ask me to do that, I would need to know what parameters and may ask for assistance with that.. But any help would be appreciated..

Tony is right on the money about everything.

 

There's no need to reflash your ECU with the map. The BASE map that is flashed stays on regardless of ECU resets/battery pulls. The REALTIME map will get wiped out with an ECU reset though.

 

So if you were say... running a basemap for 93 octane, and you loaded up a realtime map for 91 octane because you were somewhere without 93 gas and then your ECU is reset, it'll go back to 93 because that is your BASE map.

 

That shouldn't affect your idle though. So follow Tony's advice.

So Im going to try to attempt to log this thing this afternoon, its slow enough at work where I should be able to take a blast down the highway.. Im assuming I should log through all circumstances, but try to get the situation to arise, so we can see what is going on?

other than LTFT Bank 1a, anything else specific I should make sure is on there?

This is my first attempt at this so I know Im sounding like a newb.

Thanks a lot Tony

So didn't log last night, too much traffic, wanted to get home.. Today ran like crap in a.m, pulled a P0303 finally.. Was able to find the coil connector loose on my way to work.. Made it to work without too much issue, still felt shaky/rough in low RPMs.. At work took some time to pull the plugs on that bank, they looked good, cyl 3 was a little sooty, but im assuming due to misfire. Then compression tested cyl 3 and got 85psi, and cyl 1 had 100.. didn't bother doing the other bank. Put it back together and called a buddy that manages the Service dept at local subi dealer.. Car is certified but out by time not by miles, hes emailing his service rep to see if they can do anything for me. Time will tell..

In the meantime cleared the codes and memory drove car, seems to be better, but didn't get to drive it too much, had to get back into the office at work..

So at this point Ill be taking suggestions, but Im leaning towards ringland or exhaust valves- I know leakdown would confirm from where, but Im waiting to see what SOA has to say about it first.. If they don't step up, let the part out begin.

I think the damn car heard me talking to my wife about getting outta the car game for awhile till we had our own house and I had my own garage.. Ohh well its a Subi-thing, no-one else understands

Bummer man... sorry

Hoping to hear back from SOA/Dealer today.. Time will tell..

Just found your thread. :facepalm:

 

That sucks man. I hope your friend can pull the right strings to help you out. Keep us in the loop.

Hope it's good news. Regarding your compression #'s, both seem low on that bank. Head gasket? And what vacuum leak was fixed on your intake last Tuesday?

The small line from drivers side of intake to brake booster had blown off.. As far as compression Im guessing ringland or burned valve.. haven't done the leakdown to confirm top or bottom end.. waiting to see if SOA tells me to pound sand or look into it further..

These ones aren't really known for HG problems, at least not for compression leaks, sometimes for oil and coolant leaks, but they fixed the shitty HG design from the older ones, so these LGTs don't see much HG troubles.

Cracked/broken ringland or burnt valve would explain low compression on one cylinder. Actually, a burnt valve in my Volvo is why that car is sitting in the driveway and a Subaru now sits in my garage. Compression was reading about 10psi in that cylinder and the others were around 150. If your test is accurate, you're low on compression on both cylinders on that side. Granted, I'm new here and new to Subarus but from what I've read, compression should be reading in the 130's or 140's.

 

I opened this thread because I'm getting the typical stumble at idle and I've ordered new gaskets between the intake and TGV that will hopefully resolve. I was going to suggest something along these lines for you (or some other vacuum leak possibility) but it sounds like you might have bigger issues going on. Good luck, I'll be interested to see how this plays out for you.

I did those O-rings about a month ago due to fuel smell when under 20'.. You are right about where the numbers "should" be.. At this point its going to be all (engine and heads rebuild) with SOA assistance, or nothing (I'm gunna part it out and trade it in) we will see

Any update? Curious.

Mine just started to do that as well. It has yet to stall completely, but you can definitely fell the shaky/lower idle and yielded response time.

Mine just started to do that as well. It has yet to stall completely, but you can definitely fell the shaky/lower idle and yielded response time.

 

Well I'd start with vacuum leaks first with this as a known issue:

http://legacygt.com/forums/showthread.php/diy-rough-idle-cold-start-cold-temps-lgt-07-09-155325.html

 

OPs issue seems more dire unfortunately.

Hoping to hear from SOA this week. Stalls less since cleared ecu. but after sitting in traffic it does it alot. Slow speeds high loads (braking/turning in parking lots). In traffic almost feels like booster is leaking and/or idle won't adjust right.

I can almost make it do it. I going to attempt to log the event sometime this week when all the snow melts and roads are safer

Heard from SOA today. They want to look at it and tear it down to find failure. And want maintanance records which i cant provide since i do all my own work. All on my dime with no guarantees they will even pay for anything. I can't afford to get into that so I'm having underdog get me a price on rebuild, if that's not feasible away it goes..

Not too upset, its the way it works. Can't expect them to pay for every motor that fails..

Stalling is getting worse. Im going to get leak check done to make sure I'm not missing something.

Damn. Working on your quote now. Sorry to hear the bad news.

So attempted driving around the work parking lot this morning with the AP hooked up, got it to stall a few times, but was unable to really see what was going on. This part of Turbo cars is new to me (reading tuning stuff) , anyone in southeastern mass wanna take a look at this thing with me before I just pull the motor? I don't want to spend money on a shop looking at it cause I know compressions low.. Im thinking there is something else causing it to stall tho. But I have never had CEL light come on

I wish I was closer so I could just take a look while it is in the car.

Rick,

Id be more than happy to take the ride up for you to look at it on Tuesday. I just don't want to put a lot into now, considering the cost of a rebuild. If I could get it to stop stalling, it would allow me a little more time to get the money saved. LMK if you wanna take a look

Steve,

I am certainly willing to take a look, but that is a LONG drive for you to take in a car that is at risk. (~1.5 hours). PM me if you think it is worth pursuing.

-Rick