GTB hesitation

[Guest]

i have a 98 gtb bg5 legacy and now and again i get hesitation at low to mid revs just driving it normal.it mainly happens in the wet but does now and again do it in the dry and im pretty sick of it now i have changed afm several times.spark plugs were done about 9 months ago along with some coils and none a that really helped.i got a knock sensor code up so i replaced that with another 1 and the guy at wreckers told me to put in on top of the motor just in front of intercooler to the right a we bit as its easya to put back.this hesitation has been there the hole time i have owned the car but just recently got worse.i did google it and alot a people had the same trouble as me especially in the rain like mine and they moved there knock sensors from original position to another position heres a pic i got of the site that shows both positions http://imageshack.us/photo/my-images/853/knocksensorcopy.jpg/ .....has any one tried this? and why would it act up lots in the wet and not so much in the dry? i would really like to fix this problem my self asap any thoughts welcome.

[Bugle]

When did you last change the air filter?

[Guest]

 Bugle said:

When did you last change the air filter?

i changed my pod last service and i just had full service again 2day so il get another 1 i normally change air filter every service

[gazzy2000]

start with the basics:

- plugs/leads (crrect gap plugs)

- only run 98 octane petrol

- get a new Fuel filter

- clean IACV

- upper engine cleaner

- injector cleaner

- clean your battery terminals and earthing points on body and engine.

- Maybe fit earthing kit

- reset the ECU after every new sensor fitting/change/clean

a good thing to do is a new bosch universal o2 sensor as these are meant to be changed every 50-80,000 kms, the user on here called robertsm can get good priced o2s, genuine subaru around $350 he does them for like $160 -$180

I'd start by resetting the ECU after fitting a new knock sensor

The knock Sensor relocation is a good idea, as long as it torqued to 24NM

Info on the above is all on this forum i.e. how to reset ECU (properly) how to use upper engine cleaner etc etc, try a search, if you get stuck just post/ask away

[Guest]

 gazzy2000 said:

start with the basics:

- plugs/leads (crrect gap plugs)

- only run 98 octane petrol

- get a new Fuel filter

- clean IACV

- upper engine cleaner

- injector cleaner

- clean your battery terminals and earthing points on body and engine.

- Maybe fit earthing kit

- reset the ECU after every new sensor fitting/change/clean

a good thing to do is a new bosch universal o2 sensor as these are meant to be changed every 50-80,000 kms, the user on here called robertsm can get good priced o2s, genuine subaru around $350 he does them for like $160 -$180

I'd start by resetting the ECU after fitting a new knock sensor

The knock Sensor relocation is a good idea, as long as it torqued to 24NM

Info on the above is all on this forum i.e. how to reset ECU (properly) how to use upper engine cleaner etc etc, try a search

thanks man i have done most of the about but what is IACV where can it be located?and is fuel filter that square pad thing on the end of the puel pump? i have been through like 4 fuel pumps since i have owned the car about 18 months lol and yep i reset the ecu after every sensor or change i do to the car and its showing no codes.i run my car on 95 but i dont think thats the problem as it only happens every time i drive it in the rain and once n a blue moon it will do it in the dry

[ODB]

Hunted this problem down on my parents 2000 gtb and it was O2 sensor.

Replaced and no more hesitation.

[Guest]

 ODB said:

Hunted this problem down on my parents 2000 gtb and it was O2 sensor.

Replaced and no more hesitation.

did your parents 1 only play up alot in the rain?i would really like this to be the fix lol

[ODB]

it just developed a bit of a miss / hesitation early in the rev range.

TBH i couldnt tell you if it was in the wet or dry or both.

[Guest]

 ODB said:

it just developed a bit of a miss / hesitation early in the rev range.

TBH i couldnt tell you if it was in the wet or dry or both.

it does kinda make sence that it could be that as it will get very wet from the road but i have replaced the o2 befor cause the check light come on but problem was there befor that happen and still there now but i will try my mates 1 and see if it makes a difference cause that would explain why it plays up hard out in the rain cause the sensor on bottom of car.

[DRFVDR]

Ok back the fark up

you said it hesitates in the rain

u have also said you changed the POD last service

anyone else see where I am going ???

[Guest]

 DRFVDR said:

Ok back the fark up

you said it hesitates in the rain

u have also said you changed the POD last service

anyone else see where I am going ???

Your point is?

[will i am]

 DRFVDR said:

Ok back the fark up

you said it hesitates in the rain

u have also said you changed the POD last service

anyone else see where I am going ???

either he means ur sucking up water threw ya pod in the wet

or havn pod filters on these cause the afm to fuck out.

or im probably way off lol

[Joker]

check for water past your pod/in your afm, do you still have your plastic inner guards in the wheel arches?

[DRFVDR]

 will i am']

[quote name='DRFVDR said:

Ok back the fark up

you said it hesitates in the rain

u have also said you changed the POD last service

anyone else see where I am going ???

/quote]

either he means ur sucking up water threw ya pod in the wet

or havn pod filters on these cause the afm to f*** out.

or im probably way off lol

Yup I would check for water ingestion,as this will cause hesitation,also what sort of POD is it if it is a foam one it can hold water which with normal driving is all good but as soon as u stomp on it and you want the car to boost the airflow though the POD can pick up a whole heap more water and effectively puts the flame out in the combustion chamber,it is also well known that pod filters destroy AFM's.

Try every thing else as suggested but I would look at putting the original airbox back in with a CAI feeding it

[Guest]

Rite im back to factory air filter setup so il see how that gos.i had a good check over my car today everything seems fine so il let use know if that is the cure.fingers crossed.fukin TT

[Kiwi_Fozze]

factory system works better than pod anyways from what iv seen / heard / read.....