Go Back   Subaru Impreza Forum - WRX STI Rally Performance Tuning > Subaru Impreza Technical Area > Technical General

Subaru Impreza Forum

2007 STi engine issue PLEASE HELP!
Reply
 
LinkBack Thread Tools Display Modes
Old 06 Oct 2009, 07:57 AM   #1 (permalink)
Fresh Scooby
 
Join Date: Oct 2009
Posts: 18
2007 STi engine issue PLEASE HELP!

I own a 2007 subaru impreza sti and the engine timing/ignition is all over the place ranging from -14 to +60. (I have been told this range is to great)

One second the car has no power at all and then it has heaps and the nothing. The rpm is jumping all over the place when the engine does this and the car jerks forward some times quite violently.

It has been to a Subaru dealer 5 times over the past 6 weeks. They have changed the spark plugs, air fuel meter and reset the ECU.

The ONLY modification the car has is a TBE nothing else, this has been on the car for over 2 years and Subaru say this is the problem but if that was the case the problem should start as soon as or at least not long after this was fitted.

I'm desperate to get this problem fixed can anyone help.
Offline   Reply With Quote
Old 06 Oct 2009, 08:36 AM   #2 (permalink)
Obsessed Scooby
 
The Pilot's Avatar
 
Join Date: Jul 2006
Location: Bay of Tor...
Posts: 6,567
Re: 2007 STi engine issue PLEASE HELP!

take it to a tuner and get it on the the rollers for a FULL diagnostic,that way they can see exactly what the ECU,engine and everything else is doing..
__________________
Mapped by Enginetuner(Plymouth)..

Last edited by The Pilot; 06 Oct 2009 at 09:09 AM.
Offline   Reply With Quote
Old 06 Oct 2009, 08:58 AM   #3 (permalink)
Fresh Scooby
 
Join Date: Oct 2009
Posts: 18
Re: 2007 STi engine issue PLEASE HELP!

Hi Thanks for the reply

I have done this already and it showed that the air fuel meter had a different volt reading and thus was changed. But the problem still remains.

I have just picked up the car from the service dealer today and the keep saying it's the TBE but I have never ever heard of this being a problem and I did spend the money on a decent exhaust from a reputable manufacture. They have fitted the standard exhaust back on the car and I'm going to drive it for a few days and see what happens.

Any other suggestions from yourself or anyone else are greatly appreciated.
Offline   Reply With Quote
Old 06 Oct 2009, 09:13 AM   #4 (permalink)
Obsessed Scooby
 
The Pilot's Avatar
 
Join Date: Jul 2006
Location: Bay of Tor...
Posts: 6,567
Re: 2007 STi engine issue PLEASE HELP!

to be honest imo,it the ECU thats having a problem,have you got someone you know with a similar car that would be willing to try an ECU swap?
__________________
Mapped by Enginetuner(Plymouth)..
Offline   Reply With Quote
Old 06 Oct 2009, 09:29 AM   #5 (permalink)
Fresh Scooby
 
Join Date: Oct 2009
Posts: 18
Re: 2007 STi engine issue PLEASE HELP!

I hadn't thought of that I will try and give it a go.

Things I've had tested are:
-all O2 sensors
-catalytic converter / exhaust
-waste gate actuator
-spark plugs
-clutch
-air filter
-intercooler leaks
-fuel

Things I think it might be: (even though I know I'm NOT a mechanic)
-fuel filter
-ECU problem
-spark plug leads
-battery (a new one was installed a couple of months ago)
-alternator

I'm pretty sure it is an electrical issue. But who knows.
Offline   Reply With Quote
Old 06 Oct 2009, 09:42 AM   #6 (permalink)
Super Moderator
Paid & Proud
 
2002pete's Avatar
 
Join Date: Sep 2004
Location: UK
Posts: 14,377
Re: 2007 STi engine issue PLEASE HELP!

I would have said 02 sensor.

Did the engine managment light up? Your car could be in safe mode restricting your revs due to a faulty 02 sensor on the exhaust.

If it is a sensor this fault/error code should have been found via the OBDII diagnostics port.
__________________
Pete.

Offline   Reply With Quote
Old 06 Oct 2009, 09:47 AM   #7 (permalink)
Veteran Scooby
 
bugeye_bob's Avatar
 
Join Date: Mar 2009
Location: UK-Earth - Search google maps for "The Stig"
Posts: 4,567
Re: 2007 STi engine issue PLEASE HELP!

How many miles since ur last oil change fella?
Offline   Reply With Quote
Old 06 Oct 2009, 09:54 AM   #8 (permalink)
Fresh Scooby
 
Join Date: Oct 2009
Posts: 18
Re: 2007 STi engine issue PLEASE HELP!

O2 sensor has been checked and found to be fine.

I did have a PO420 fault code (catalytic converter fault) a couple of months ago but it has been checked and cleared. Haven't had a problem since.

It is due of a 75K service very soon but I don't believe that should be an issue.
Car is serviced by the book and I always use Motul 300V 10w40.
Offline   Reply With Quote
Old 06 Oct 2009, 09:58 AM   #9 (permalink)
Veteran Scooby
 
bugeye_bob's Avatar
 
Join Date: Mar 2009
Location: UK-Earth - Search google maps for "The Stig"
Posts: 4,567
Re: 2007 STi engine issue PLEASE HELP!

Its just that the avcs is oil pressure controlled and ur timing is all over the place, I wondered if the oil relief valve is working correctly, old or the wrong oil can cause this type of fault.
hth

edit to add: you would think a sensor fault would have been stored in the DTC`s or shown up live.

Last edited by bugeye_bob; 06 Oct 2009 at 10:02 AM.
Offline   Reply With Quote
Old 06 Oct 2009, 10:25 AM   #10 (permalink)
Fresh Scooby
 
Join Date: Oct 2009
Posts: 18
Re: 2007 STi engine issue PLEASE HELP!

Sound like an idea it is sound thing else I will add to the list of things to get checked.

Is this something I check it myself? Where is it located?
Offline   Reply With Quote
Old 06 Oct 2009, 11:16 AM   #11 (permalink)
Super Moderator
Paid & Proud
 
2002pete's Avatar
 
Join Date: Sep 2004
Location: UK
Posts: 14,377
Injector stuck open/not performing correctly.


If it was just a idle problem.

1: Air control solenoid valve.
2: Vacuum leak.
3: MAF failure.
__________________
Pete.

Offline   Reply With Quote
Old 06 Oct 2009, 12:04 PM   #12 (permalink)
Fresh Scooby
 
Join Date: Oct 2009
Posts: 18
Re: 2007 STi engine issue PLEASE HELP!

MAF and vaccum leak can be ruled out as they have been checked by Subaru.
Not sure if solenoid valve has been checked.

The problem I have is very ill regular and in consistent that's why I don't think it is a spark plug (which they changed) or injector issue. I have a scan gauge linked to the car, this is how I know the ignition timing is all over the place. Boost, volts etc seem normal.

It is very hard to explain one minute i'm driving along and I press the accelerator and the revs but has no power. This same situation can happens down the road again accept this time it might jerk forward as if not letting the clutch out properly (Clutch is fine and has been checked) then it might happen again and the car will have power after a few seconds.

I have trolled through the internet for the past 2 months and can't find anything that relates to this situation. I finally cracked the shits at Subaru today and have posted this topic up on 4 forums.

Once again all help/ideas are appreciated.
Offline   Reply With Quote
Old 06 Oct 2009, 12:54 PM   #13 (permalink)
Super Moderator
Paid & Proud
 
Tidgy's Avatar
 
Join Date: Apr 2006
Location: Nottingham
Posts: 18,743
Re: 2007 STi engine issue PLEASE HELP!

my advice would be to get it to a specialist and get them to take a look, start from the complete basics and do a full workup, compression test, check the timing is correct, alternator voltage, check the sparkers, coil packs, boost leaks etc etc.
__________________
PM, Squirrels best friend, cream egg king and resident .org spam tart/Perv
Offline   Reply With Quote
Old 07 Oct 2009, 10:43 AM   #14 (permalink)
Fresh Scooby
 
Join Date: Oct 2009
Posts: 18
Re: 2007 STi engine issue PLEASE HELP!

From my understanding I thought this is what they have already done being a STi Dealer.
Plus the performance shop I had been to when I put it on the rollers. $$$

But I doubt it from all the trouble I'm having.
Offline   Reply With Quote
Old 07 Oct 2009, 10:53 AM   #15 (permalink)
Obsessed Scooby
 
The Pilot's Avatar
 
Join Date: Jul 2006
Location: Bay of Tor...
Posts: 6,567
Re: 2007 STi engine issue PLEASE HELP!

where have you taken the car??
__________________
Mapped by Enginetuner(Plymouth)..
Offline   Reply With Quote
Reply

Bookmarks


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
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
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Oil advice for modifiers oilman Modifications - Tips and Tricks 16 14 Jul 2009 03:40 PM
16 important OIL questions and answers oilman Technical General 0 23 Jan 2008 03:31 PM
OUTSTANDING NEW ‘BOXER’ ENGINE FOR ’06 LEGACY RANGE skylight General Chat - Anything about Anything 3 03 Aug 2005 10:15 AM


All times are GMT. The time now is 09:53 PM.



Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
LinkBacks Enabled by vBSEO 3.6.0 PL2 © 2011, Crawlability, Inc.