Engine problem Lib GT-B

[thissoan]

Have recently noticed an annoying engine problem with my MY08 Lib GT spec B with 5spd auto. Under full load or full open throttle the engine intermitedly cuts out or pauses during hard acceleration. Seems to occur more frequently in sports sharp manual mode (3rd gear) on cold mornings. No mods on engine or intake. Has anyone got any simular occurrences and solutions or any advise as to what may be the problem before I go to Subaru and break their balls (still under warranty). Any good advice appreciate.

Cheers Thissoan.

[senator]

does your engine light come on?

[Kekotic]

Someone suggested in a similar thread to reset the ECU. Disconnect the battery for 10 minutes and press on the brake a few times.
You will lose your radio settings by doing this.

[jdm rsk]

Could it be boost/fuel cut due to over boost

[thissoan]

Thanks for the replies. I'm not getting a check engine light and have recently reset the ecu. I have no idea about any over-boost issues. I've hooked up a scan-gauge ecu reader and its indicating an unusual amount of ignition retarding on a 3rd gear acceleration run which kicks in at about 3000rpm. Drops by 20 degrees, I'm thinking faulty knock sensor??? Would appreciate any thoughts or past observations. The only modification on my GT-B is a pair of hitech quad tip diffback mufflers, everything else is stock.

Cheers
Thissoan

[jp928]

Knock sensor sounds right culprit - it was in my Outback - but my ecudatascan says there is no knock sensor data avaiable in the 08 gt, so I dont know how it works out ignition correction. I have had a few cases of hesitation in mine , going from backed off and slow to lots of accelerator (6mt), but using 98Octane seems to keep this issue away. Your problem sounds different, if it occurs in 3rd, when the speed should be up some.
What sort of rpm is it doing when this occurs?
jp 08 gtb 6mt wagon.

[SillySora]

Does yours change from 3rd to 4th without you doing it. This is what mine does under full load about 5000 rpm will just change to 4th.

[swingn]

Could it be boost/fuel cut due to over boost

+1

If you've had your car tuned, then it generally won't throw an engine light... But if your car is untouched, then it should throw up something which will then go away after it's turned on & off 5 times.

[thissoan]

Knock sensor sounds right culprit - it was in my Outback - but my ecudatascan says there is no knock sensor data avaiable in the 08 gt, so I dont know how it works out ignition correction. I have had a few cases of hesitation in mine , going from backed off and slow to lots of accelerator (6mt), but using 98Octane seems to keep this issue away. Your problem sounds different, if it occurs in 3rd, when the speed should be up some.
What sort of rpm is it doing when this occurs?
jp 08 gtb 6mt wagon.

Usually around 3000rpm on a loaded throttle from a low speed run. I reckon you are right my friend about the knock sensor.

[thissoan]

Does yours change from 3rd to 4th without you doing it. This is what mine does under full load about 5000 rpm will just change to 4th.

Yep sure does. Do you know why this happens??

thissoan

[SillySora]

My mate was saying something to do with the auto. Solenoids sending signals to change.

Mine has been tuned so not sure if it is a boost cut fuel cut, cause my still goes not that sudden cut off.

I also think not sure if it is true but the way you drive the ecu learns, generally I will back off around then so the auto just changes into 4th. Not sure if this is true but when the battery has been disconnected it usually doesn't do it. This caused me a lot of issues at Jambo was too lazy to reset the battery.

Looks like the only people I know that can do good stuff with the auto are in the us

Also like to add mine did this on stock also with 98 octane every now and then but.

[jp928]

Here's another though FWIW - in the Outback I had (5mt, and I realize its not turbo, different almost everything), dealer made a big thing about the fuel treatment stuff going in at service, and at 6k in between. Once when I had bad stuttering around 6k in, I put the treatment in, and filled the tank. Within 1km the sturrering/hesitation disappeared completely, transformed the engine into something nice to drive. This model had a discrete knock sensor bolted to the block, and I was able to long term remove the hesitation by putting a rubber washer under the sensor (based on web stuff from US users) - over active sensor?
Anyway, can I suggest you try a dose of this sort of stuff and see - many i have seen recommend Caltex Techron.
Curiously, while my lease co Orix are happy for a service to include the fuel treatment, they refuse to wear the cost of the 6k intermediate dose being included at service time....
Mine is nearly at the 62.5k service, and just this morning when I went to stamp on the pedal, I got an initial surge, then a small but noticeable reduction in urge, then it came back in with a vengeance - bit like an up change in auto, but its 6mt. Will report it , and see what happens after the service...

jp 08 gtb 6mt wagon.

[SillySora]

This is something that I need. Not sure how to or where to get this done. I emailed them hopefully will be able to see if anyone in Aus can do this.

http://www.importperformancetrans.com/subaru5eat.shtml


I know the America forums of the libs a lot of guys are using this.

[jdm rsk]

This is something that I need. Not sure how to or where to get this done. I emailed them hopefully will be able to see if anyone in Aus can do this.

http://www.importperformancetrans.com/subaru5eat.shtml


I know the America forums of the libs a lot of guys are using this.

me 2 shane

[SillySora]

Also found this http://legacygt.com/forums/showthread.p ... 40461.html


But taken this to a Subie dealer >< and re-setting the tcu could be costly.

Might give it ago as the 5eat gearbox is pretty strong.


Also my mate had the same issue in his 1jz corona but there were people who could fix this and just manualized it. Turned the solinodes off or something.