2008 STi Starts Normally and Then Immediately Dies - Subaru WRX Forum
 2Likes
  • 2 Post By boo-key bear
 
LinkBack Thread Tools Display Modes
#1 Old 02-09-2014, 10:57 AM
WRXtuners Member
 
Join Date: Feb 2014
Posts: 2
f4ight is an unknown
2008 STi Starts Normally and Then Immediately Dies

Out of the blue my 2008 STi will start normally, shoot for 1500 RPM, and then immediately die. I drove the car the night before and everything was fine and went to start it in the morning and it won't stay lit. Nothing appears to be wet under the hood but we did have light rain that evening.

Video with my foot off the pedal

Video with my foot on the pedal ~10% (same thing happens even with a jump start)

Under hood picture with the location of where I measured fuel pressure marked in yellow
https://dl.dropboxusercontent.com/u/...209_081338.jpg

The car is a 2008 STi with 19,000 miles, GT3076R turbo, custom up/down pipes, FMIC, Abaco 85mm MAF, DeatschWerks 850cc fuel injectors, Walbro GSS342 fuel pump, and Crawford air to oil separator kit. It has run strong since I bought the car without any starting problems. For about a month I have had a random and mildly rough idle that I attributed to plugs but hadn't gotten around to changing them.

Things I have done and then tried to restart it:
Jump starting it with another car since the battery was low
Resetting the ECU (checked for codes first)
Uninstalling the Access Port reverting back to stock calibration
Reinstalling the calibration
Disconnecting the battery
Using my two other set of keys
Disconnected the MAF
Reconnected the MAF
Checked fuel pressure and stays at ~45 psi (see pic for hose I tapped into)
Replaced spark plugs with new NGK Iridiums
Checked for obvious loose parts or split plumbing

There was no change whatsoever even when putting it back to the stock calibration which is weird because it has a different MAF and injectors.

Things I have monitored via Access Port:
MAF, starts in the dirt and goes up after starting
MAP, starts at baro and goes down after starting
Crank SW: starts at 0 and goes to 1 after starting
Cam SW: starts at 0 and goes to 1 after starting
Intake temp: close to ambient
Coolant temp: close to ambient
Inj PW: starts low, goes up after starting
Calculated load: starts low, goes up after starting (0.4 g/rev)
Timing: Within normal range
There are no codes stored. The only code that came in was after I disconnected the MAF and received a intake temp code.

Nothing seems out of the ordinary but the thing just won't stay lit. It is almost acting as if the ECU is shutting it down after a prescribed amount of time because of how repeatable it is. I have now tried to start the car a 100 or so times and it does the same thing every time. It also seems like it has a fixed amount of fuel and timing it will provide until the crank and the cam are synchronized and then it falls on its face.

Ideas, thoughts, magic? Thanks in advance.
f4ight is offline  
Sponsored Links
Advertisement
 
#2 Old 02-09-2014, 07:55 PM
WRXtuners Member
 
Join Date: Feb 2014
Posts: 2
f4ight is an unknown
FIXED!

Ok, temporarily fixed. Un-####ing-believable that a single resistor on an aftermarket MAF can stop a car from running.

Pulled the MAF just to make sure the connector was clean and to spray down the elements while I was there. Looked inside to see half of a 5.1 ohm resistor hanging by one pad. No idea how it got hot enough to melt the solder and move off the pad or how half of it broke and fell into the air filter. Total jimmy-rigged two 2 ohm resistors in series with another two in parallel to kinda make 5 ohms, soldered it in and it started and ran. For giggles and shits I pulled the MAF connector after the car was running and it died. No Alpha-N or Speed Density limp home whatsoever. Really lame on Subaru's part or the tuners part for not applying the corrections to the limp maps.

Before... https://dl.dropboxusercontent.com/u/5085/Before.jpg

After... https://dl.dropboxusercontent.com/u/5085/After.jpg

I ordered a new resistor for a buck and will put it in this week to see if there was just a freak failure of the component.
Invalid Request

If it dies then I am stuck with a new MAF from summit is $379. Boo.
http://www.summitracing.com/parts/aa...bx85/overview/

This was a terrible way to waste the better part of 2 days.
f4ight is offline  
#3 Old 02-09-2014, 09:58 PM
Premium Member
 
boo-key bear's Avatar
 
Join Date: Dec 2008
Location: Tennessee
Posts: 1,072
Images: 6
boo-key bear is a helpful contributing member
Garage
Thanks for sharing the fix. Its always nice when someone fills the forum in on what the problem was instead of just never returning.
turmic and arewmors like this.

Adair
06' wrx tr
Phatbotti tuned!
boo-key bear is offline  
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



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 Off
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On