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Gt foz idling rough/surging

Posted: Sat Mar 05, 2016 1:11 pm
by outback_98
Hi all so my 2000 gt forester has been playing up, started with little surges at 100k, did few times then went away.So then started idling rough and occasionally stalling just after starting.So have changed fuel and air filter leads and was told maybe the coil do that also.Still coughing😢 Please need advice!

Posted: Sat Mar 05, 2016 8:11 pm
by yarney
Have you done an upper engine clean if not try that
Only use Subaru upper engine cleaner

Jan

Posted: Sat Mar 05, 2016 8:38 pm
by outback_98
no,shall try

Posted: Sun Mar 06, 2016 10:16 pm
by El_Freddo
Clean/inspect your idle air control valve as this could be causing the issue.

Also have the ECU code read to see what pops up ;)

Cheers

Bennie

Posted: Wed Mar 09, 2016 4:36 pm
by outback_98
have tried everyone in our area no one has a tool that will read my model,we in the sticks lol most are saying o2 sensor?? did the upper engine clean was no better after?

Posted: Wed Mar 09, 2016 8:12 pm
by Proton mouse
Ditto on the iacv. Different varieties of them on different EJ motors so do a bit of googling and YouTubing to find a 'how to remove' on yours. Then use that upper end cleaner to clean it out.
Dodgy O2 sensor usually makes engine just run rich, which doesn't seem to be your symptoms.
Not familiar with your model, but there should be some diagnostic plugs under dash you join together which will then give you a fast and slow flashing light on dash, which are the ECU error codes, in code!! 1 long flash is 10. 1x short flash is 1. So eg. 2 long flashes followed by 4 short flashes would be 24
Google the error code list for your engine model and you'll know the problem!! Good luck!!
Cheers JB

Posted: Sun Mar 13, 2016 2:37 pm
by outback_98
have now ran cleaner,cleaned throttle and changed sensor,am now being lead to believe it could be the TPS,the symptoms sound like what it is doing for sure

Posted: Sun Mar 13, 2016 3:59 pm
by outback_98
Also its a 02/00 gt foz,i see a obd2 plug have been told by 2 mechanics that their tool wont read it? although they fit my 03lib RX ???

Posted: Mon Mar 14, 2016 11:24 am
by outback_98
got a scanner to read it,threw no codes but the maifold pressure was all crazy so looks like map sensor,which was replace 2 years ago :/

Posted: Mon Mar 14, 2016 3:31 pm
by Subydoug
If you got one, compare your map sensor to a mechanical engine vac gauge. Map sensors are pretty sensitive and the rough running engine could be the cause of the bad map readings. Does the map signal smooth out with the engine? Ie steady revs at 2k?

Regards

Doug