Welcome to the North American Subaru Impreza Owners Club Thursday April 17, 2014
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Here you can view your subscribed threads, work with private messages and edit your profile and preferences Home Registration is free! Visit the NASIOC Store NASIOC Rules Search Find other members Frequently Asked Questions Calendar Archive NASIOC Upgrade Garage Logout
Go Back   NASIOC > NASIOC Technical > Built Motor Discussion

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.
* Registered users of the site do not see these ads.
Reply
 
Thread Tools Display Modes
Old 03-29-2009, 12:25 AM   #1
generalee69
Scooby Specialist
 
Member#: 106470
Join Date: Jan 2006
Chapter/Region: NWIC
Location: Kent WA
Vehicle:
2004 STI ICSCC #9
www.ClintonRacing.com

Default Trackday issue ... WTF?!

I got my car out to the track for the first time since the motor was rebuilt. On the third session I had a little issue that I can't figure out.

About 5 laps into the session, the car felt like it was misfiring in 3rd gear at WOT and high RPM (5000ish+). On that lap it only "misfired" once. On the next lap it did it a couple of times in 3rd and 4th in the same section of the course.

Each time the misfire occured I would immediately up shift. When I up shifted the misfire would quit.

On the following lap it started misfiring and I just kept my foot in it and popped a CEL.

I immediately pulled into the pits.

When I opened the hood the only thing I could find was that the expansion tank lid was not completely tight, and coolant was leaking out.

I tightened the cap down and reset the ECU. On the next session I only ran at half to 3/4 throttle, no issues. No CEL, no misfire. On the last session I ran the thing as hard as I could, full WOT. No CEL, no misfire.

So my question....
Could/would the coolant leaking out drip onto the spark plug coils and cause a misfire??

Or do I have a bigger problem facing me?

Is it possibly the dreaded boost cut out issue? I have heard that when this is a problem, the engine just loses power. Not really a "misfire" feel.
* Registered users of the site do not see these ads.
generalee69 is offline   Reply With Quote
Old 03-29-2009, 12:41 AM   #2
mick_the_ginge
Citizen Mick
 
Member#: 27646
Join Date: Oct 2002
Chapter/Region: NWIC
Location: Portland, Oregon
Vehicle:
2003 Sleeved 2.5
Oil Dry Sump Goodness

Default

What EM? Was the CEL for miss fire?

Do you have a fuel surge tank? If not what was the fuel level?
mick_the_ginge is offline   Reply With Quote
Old 03-29-2009, 12:46 AM   #3
generalee69
Scooby Specialist
 
Member#: 106470
Join Date: Jan 2006
Chapter/Region: NWIC
Location: Kent WA
Vehicle:
2004 STI ICSCC #9
www.ClintonRacing.com

Default

Quote:
Originally Posted by mick_the_ginge View Post
What EM? Was the CEL for miss fire?

Do you have a fuel surge tank? If not what was the fuel level?
Cobb AP stage 2

I don't know what the CEL was.. I reset the ECU to see if I could replicate the issue. I fully expected the misfire and CEL to show up again!

No surge tank. I don't think. Sorry for being ignorant, but I haven't touched the fuel system... so unless there is an OE surge tank then no. Fuel level was about 1/2 tank.

It was also extremely wet today, rained all day, with standing water on the track.
generalee69 is offline   Reply With Quote
Old 03-29-2009, 01:07 AM   #4
mick_the_ginge
Citizen Mick
 
Member#: 27646
Join Date: Oct 2002
Chapter/Region: NWIC
Location: Portland, Oregon
Vehicle:
2003 Sleeved 2.5
Oil Dry Sump Goodness

Default

1/2 a tank of gas and a wet day rules out high G starvation (which was always an issue with my WRX before the surge tank)

It could have been water/coolant related. Water in the intake going across the MAF can screw up the fueling whuich could lead to hiccups. CAI? I had a bad connection on one of the pins in the master wiring harness plugs in the engine bay. That drove me mad for a couple of days before I tracked it down.
mick_the_ginge is offline   Reply With Quote
Old 03-29-2009, 01:12 AM   #5
generalee69
Scooby Specialist
 
Member#: 106470
Join Date: Jan 2006
Chapter/Region: NWIC
Location: Kent WA
Vehicle:
2004 STI ICSCC #9
www.ClintonRacing.com

Default

Stock intake.

The fender liners are removed and I didn't have the splash tray on today.

Also, there was water in the interior sloshing around.

It really only seemed to misfire/hiccup coming out of a corner at WOT and high rpm.... Maybe it would have started happening on the front straight if I would have stayed out longer, but who knows.
generalee69 is offline   Reply With Quote
Old 03-29-2009, 09:56 AM   #6
TopSpeed
Former Vendor
 
Member#: 78884
Join Date: Jan 2005
Location: Alpharetta, GA
Vehicle:
Go faster
at TopSpeed

Default

Fuel starve

/Tread
TopSpeed is offline   Reply With Quote
Old 03-29-2009, 11:11 AM   #7
mick_the_ginge
Citizen Mick
 
Member#: 27646
Join Date: Oct 2002
Chapter/Region: NWIC
Location: Portland, Oregon
Vehicle:
2003 Sleeved 2.5
Oil Dry Sump Goodness

Default

Ok, so WOT and High RPM... it was not that wet then. Which way was the corner? If it was to the right them we are back to fuel starvation. Remember the pump and pickup are on the passenger side of the car. Right hand turns slosh the fuel away from the pickup and it can such air if even a part of the pickup filter is exposed.

If you install a fuel pressure gauge then you will be able to debug this issue quicker, that's what I did. I would get this all the time on 12 at PIR, long, fast, High G right hander. When it would happen I would see the fuel pressure hiccup.
mick_the_ginge is offline   Reply With Quote
Old 03-29-2009, 12:42 PM   #8
02WRX2.5
Scooby Specialist
 
Member#: 63192
Join Date: Jun 2004
Chapter/Region: NWIC
Location: Portland, Or
Vehicle:
02 wrx
157mph trap

Default

Lack of fuel main reason i won't get out on that track again till I complete fuel system, I think a half tank in not attequate for track time unless you have surge tank. high enough G's and you will starve your fuel pickup.
02WRX2.5 is offline   Reply With Quote
Old 03-29-2009, 01:20 PM   #9
generalee69
Scooby Specialist
 
Member#: 106470
Join Date: Jan 2006
Chapter/Region: NWIC
Location: Kent WA
Vehicle:
2004 STI ICSCC #9
www.ClintonRacing.com

Default

I fully appreciate all of the experience that you guys have to help me assess my problem.

What just doesn't make sense to me is that I have run the car in a lot harder more demanding situation with LESS fuel and I have never experienced this before. I was on Dunlop Direeza's in the wet when this occured, compared to the same track in the dry on Hoosiers last season...

The fuel pressure gauge is a good place to start though.

But no one thinks that the water leaking from the expanison tank or a bad engine/chassis ground could cause this issue?

I'm a little irritated now that I could not get the problem to replicate in the following sessions so that the CEL would came back.

Another stupid question, once the ECU is reset it is impossible to retrieve the latest CEL code corret?

Last edited by generalee69; 03-29-2009 at 02:48 PM.
generalee69 is offline   Reply With Quote
Old 03-29-2009, 01:28 PM   #10
generalee69
Scooby Specialist
 
Member#: 106470
Join Date: Jan 2006
Chapter/Region: NWIC
Location: Kent WA
Vehicle:
2004 STI ICSCC #9
www.ClintonRacing.com

Default

Quote:
Originally Posted by mick_the_ginge View Post
Ok, so WOT and High RPM... it was not that wet then. Which way was the corner? If it was to the right them we are back to fuel starvation. Remember the pump and pickup are on the passenger side of the car. Right hand turns slosh the fuel away from the pickup and it can such air if even a part of the pickup filter is exposed.

If you install a fuel pressure gauge then you will be able to debug this issue quicker, that's what I did. I would get this all the time on 12 at PIR, long, fast, High G right hander. When it would happen I would see the fuel pressure hiccup.
Actually... this slosh would make sense becuase it seemed to happen after the kinks in the track (right then immediate left). What doesn't really align with the slosh theory is that it would happen after the car had straightened out after the cornering... unless there is a little bit of a delay from the time the pickup starts sucking air to the time the engine sees the effects.
generalee69 is offline   Reply With Quote
Old 03-29-2009, 01:34 PM   #11
generalee69
Scooby Specialist
 
Member#: 106470
Join Date: Jan 2006
Chapter/Region: NWIC
Location: Kent WA
Vehicle:
2004 STI ICSCC #9
www.ClintonRacing.com

Default

Quote:
Originally Posted by mick_the_ginge View Post
Ok, so WOT and High RPM... it was not that wet then.
A quick pic from yesterday




Pretty wet, I haven't heard how much rain we got yesterday but it had to be more than a half inch (bordering an inch probably).
generalee69 is offline   Reply With Quote
Old 03-29-2009, 03:37 PM   #12
mick_the_ginge
Citizen Mick
 
Member#: 27646
Join Date: Oct 2002
Chapter/Region: NWIC
Location: Portland, Oregon
Vehicle:
2003 Sleeved 2.5
Oil Dry Sump Goodness

Default

Quote:
Originally Posted by 02WRX2.5 View Post
Lack of fuel main reason i won't get out on that track again till I complete fuel system, I think a half tank in not attequate for track time unless you have surge tank. high enough G's and you will starve your fuel pickup.
Matt, I thought the real reason was that you can only drive in a straight line

I would go over all the electrical plugs with that contact solution to ensure they all have a good connection just incase. Unplug them, spray them, then plug them back in/out a couple of times.

Their is typically a small delay between the "starve" event and the engine hiccup. I would be almost out of 12 on PIR before the lean miss would happen.

An ECU reset clears both the realtime and stored codes, sorry the code is gone.

That wing is huge.............

Another thought
You are not overboosting are you? A P0244 (overboost) will cut the boost control solenoid....... But this would be more of a brick wall rather than a hiccup.

Oh to be a stage 2 again. When I go to WOT in the rain my tires spin.
mick_the_ginge is offline   Reply With Quote
Old 03-29-2009, 03:55 PM   #13
generalee69
Scooby Specialist
 
Member#: 106470
Join Date: Jan 2006
Chapter/Region: NWIC
Location: Kent WA
Vehicle:
2004 STI ICSCC #9
www.ClintonRacing.com

Default

Quote:
Originally Posted by mick_the_ginge View Post
I would go over all the electrical plugs with that contact solution to ensure they all have a good connection just incase. Unplug them, spray them, then plug them back in/out a couple of times.

Their is typically a small delay between the "starve" event and the engine hiccup. I would be almost out of 12 on PIR before the lean miss would happen.

An ECU reset clears both the realtime and stored codes, sorry the code is gone.

That wing is huge.............

Another thought
You are not overboosting are you? A P0244 (overboost) will cut the boost control solenoid....... But this would be more of a brick wall rather than a hiccup.

Oh to be a stage 2 again. When I go to WOT in the rain my tires spin.
I'll definitely double check all the connectors.

I think I may have experienced the fuel starve at PIR out of 12 back in September. At my shift point out of 12 from 4th to 5th before the bridge, it felt like the engine had no power. I clutched in and out and it was fine. But no stutter or sputter or misfire. Then again the engine was about to kill a ringland, sooo maybe not.

As far as the code being erased, that was my understanding... I just wanted to verify.

Overboosting was the other question. A friend of mine was at the track with me yesterday that has a track prepped STi also. He was having the boost cut issue last year at Pacific Raceways. The way he described it though it was just as if the engine would sort of run out of power and bog down...then the power would come back. Not big stutter or misfire.

My issue definitely was a "wall" but it wasn't a smooth wall.

Now I can say to almost anyone "My wing is bigger than yours" he he he

I was pretty smooth on the power out of the corners, it would for sure wheel spin and want to get sideways occasionally. But once it got hooked up in a straight line I could get my foot in it all the way and it would really take off like a bat outta hell. I could gain on people a few hundred feet on people in a very short amount of time. God I love AWD in the rain I felt like such frickin hot s#^# out there

To make this post even longer -- Does anyone know what code it will throw if it was fuel starvation?

Last edited by generalee69; 03-29-2009 at 06:54 PM.
generalee69 is offline   Reply With Quote
Old 03-29-2009, 03:59 PM   #14
generalee69
Scooby Specialist
 
Member#: 106470
Join Date: Jan 2006
Chapter/Region: NWIC
Location: Kent WA
Vehicle:
2004 STI ICSCC #9
www.ClintonRacing.com

Default

Quote:
Originally Posted by mick_the_ginge View Post
I would go over all the electrical plugs with that contact solution to ensure they all have a good connection just incase. Unplug them, spray them, then plug them back in/out a couple of times.
It's just too weird of a coincidence that with all the water sloshing around in the interior, plus the expansion tank boiling over, plus the symptoms going away on the next session to NOT being an electrical short... ?

Just wishful thinking on my part until I can get some hard data via a code to go off of I know.
generalee69 is offline   Reply With Quote
Old 03-29-2009, 04:04 PM   #15
mick_the_ginge
Citizen Mick
 
Member#: 27646
Join Date: Oct 2002
Chapter/Region: NWIC
Location: Portland, Oregon
Vehicle:
2003 Sleeved 2.5
Oil Dry Sump Goodness

Default

No direct code for fuel starve, just miss fire code from running lean
mick_the_ginge is offline   Reply With Quote
Old 03-29-2009, 06:52 PM   #16
generalee69
Scooby Specialist
 
Member#: 106470
Join Date: Jan 2006
Chapter/Region: NWIC
Location: Kent WA
Vehicle:
2004 STI ICSCC #9
www.ClintonRacing.com

Default

You know... now that I think about it. This reminds me a lot of what it felt like when the O2 sensor went bad at Pacific. The only difference is that when I brought the car in and it cooled down, when I went back out on course the same misfire/stutter came back.

It's just really weird that I had no problems at all for the first two session, half way through the third session things start acting up, then the 4th and 5th sessions no problems again.

I have a friend with an STi, he lost two O2 sensors due to a faulty ECU.
generalee69 is offline   Reply With Quote
Old 03-29-2009, 08:04 PM   #17
AWDboostADDICT
Scooby Newbie
 
Member#: 196257
Join Date: Dec 2008
Vehicle:
02 wrx 354 whp RIP
10' genesis coupe

Default

that was the way my car felt when the coils were going bad.
at first it would only happen on cold days when I boost creeped in 3-4-5 gears. then it started happening any wot pull in 3-4-5 gears. then it started happening in second. and finally it got to the point that it misfired once I started to hit positive boost pressures.
AWDboostADDICT is offline   Reply With Quote
Old 03-29-2009, 08:18 PM   #18
generalee69
Scooby Specialist
 
Member#: 106470
Join Date: Jan 2006
Chapter/Region: NWIC
Location: Kent WA
Vehicle:
2004 STI ICSCC #9
www.ClintonRacing.com

Default

Quote:
Originally Posted by AWDboostADDICT View Post
that was the way my car felt when the coils were going bad.
at first it would only happen on cold days when I boost creeped in 3-4-5 gears. then it started happening any wot pull in 3-4-5 gears. then it started happening in second. and finally it got to the point that it misfired once I started to hit positive boost pressures.
hmm.... interesting. Would it do it consistently in the cold? and then consistenly in WOT? and just get progressively worse?

Were you on a track or on the steet?

That is still what I think was weird is that once it started misfiring during the third session it got worse over the course of a couple of laps. Then the next two sessions no issues.
generalee69 is offline   Reply With Quote
Old 03-30-2009, 06:21 PM   #19
generalee69
Scooby Specialist
 
Member#: 106470
Join Date: Jan 2006
Chapter/Region: NWIC
Location: Kent WA
Vehicle:
2004 STI ICSCC #9
www.ClintonRacing.com

Default

An AFR gauge would tell me if it is running lean when it misfires correct?

Obviously it wouldn't tell me if the fuel pressure is dropping due to starvation, but it would at least point me in the direcion of a lean misfire which is what a fuel starve would be also, correct?

I have an Innovate LC-1 AFR gauge that I was planning to install before I get to PIR next month. Maybe I skip the fuel pressure gauge, until the problem replicates it self...??

Just sort of thinking out loud hear.

Of course if money were no object I'd run out and get a fuel pressure gauge setup and a surge tank, but the budget is already skimpy enough trying to get everything else ready to go.
generalee69 is offline   Reply With Quote
Old 04-09-2009, 03:26 PM   #20
generalee69
Scooby Specialist
 
Member#: 106470
Join Date: Jan 2006
Chapter/Region: NWIC
Location: Kent WA
Vehicle:
2004 STI ICSCC #9
www.ClintonRacing.com

Default

So a little update if anyone is interested..

Apparently the Cobb APv2 has data logging capability. A revelation to me... but then again I'm an idiot

I'll go out this afternoon and try to get some data, but I haven't been able to replicate the problem on the street or during the final two sessions at the track.

At the very least I should be able to data log during the race weekend and if I encounter the problem again it should show up.

I'm am starting to think that maybe it was just the infamous over boost problem. According to Cobb's website for Map Notes

"If you receive a P0422 CEL accompanied by the engine cutting out, like a rev limiter, under full throttle; you are producing beyond safe levels of boost with this mapping and you will need to use the LWG version of this map."

I don't know if has anything to do with my problem, but I am using an ACT streetlite flywheel now also along with .020 over forged pistons.

Still doesn't make sense why if it was an overboost problem it would show up magically in the middle of one session and then never again....
generalee69 is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
car lost power mid-trackday. timing belt issue? HELP! dLo R6 Factory 2.0L Turbo Powertrain 22 03-05-2009 04:56 AM
CUSCO TARMAC center diff issues WTF !!!!!!!!!!!!! SKUNK2.5 Transmission (AT/MT) & Driveline 23 03-02-2009 03:40 PM
Access is denied. Vista issues.. WTF Hazdaz Off-Topic 4 10-20-2007 06:15 PM
Tech issues with AutoX/Trackdays running Water/Meth Injection? spritefiend Motorsports 8 08-23-2007 02:48 PM
brake issue after trackday on STI (cracked pad) yong22 Brakes, Steering & Suspension 14 12-22-2006 02:18 PM


All times are GMT -4. The time now is 12:22 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2014 Axivo Inc.
Copyright ©1999 - 2014, North American Subaru Impreza Owners Club, Inc.