One is an air fuel ratio sensor, down at the bottom right corner before the uppipe, one is an exhaust gas temperature sensor, or pyrometer, only fitted to the uppipe of Bugeye WRX's, which when the pre-cat fails, usually gets damaged and logs a code. The rear o2 sensor is way down by the back of the gearbox, and doesn't affect air fuel ratios.
If there was a leak before the A/FR sensor it could cause what your talking about.

Maybe something like a loose manifold bolt

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Its just the internet dude, its not real.
F.B. Racing
01 WRX (STI badged)
2010 XR5 Focus
06 Impreza Hatch 2.0i

Yeah that's true johnvk7 i don't really know xD sorry didn't mean to offend u.
-'Although, if its broken up, the car will idle poorly and struggle to generate any boost.'

It was horrendous not to long ago, idle was shocking it would stall constantly and 1st and 2nd where jumpy as hell. But after having the front pre-cat (Air-fuel) o2 sensor replaced by asg it feels A LOT better, however the car does idle with a 'flutter' and when i do hit boost it is weaker and i hear a distinct fluttering air noise also. (Plus my temp gauge will slowly go into the red within 5min of driving.. funny thing is when i boost it, it goes back down to half..)

-mao
As for the boost.. the car has a electronic boost controller but no 'control unit' ? inside the car.. also don't have a boost gauge, although there is all the wiring for defi gauges..just without the gauges lol. Just got the car a little while ago so work in progress!

I think my best bet is to bring it in to ASG then.. as removing my down-pipe etc is something I'm not 2 comfortable with just yet. Unless anyone wants to lend a hand? :P otherwise thanks heaps for all the info and helps guys!

-Matt

I will give you a hand to pull off your down / dump pipe if you like. I took mine off a couple of days ago to check a couple of things and put it back on again.

It took a couple of hours due to stiff bolts on the back of the turbine housing. If you do want a hand PM me and i would be happy to help ya. Probably a good idea to get a new gasket, for between the turbine and the dump pipe connection too, if you want to do a DIY

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Cheers,

Simon.

Will be happy to clean up the wiring for you if you let me have the wires. :P good spares for the discontinued defis.

Anyway sounds like you bought the car from someone who just ripped off everything he could take (even if the parts couldn't function without the other parts in the engine bay which he was not confident to rip off) and simply threw the car to ya.

WORD OF CAUTION: Get it fixed straight away--- do not boost this car while driving!!!!
Qn: Why have these problems not been fixed right away? I've got no clue.

Also get that fluttering noise fixed.
1)I do hope it is not a knocking noise.

2) Also,that could be coming through the airfilter. Check your air recirculation valve or blow-off valve and make sure it functions. Normally when you go on boost and let go the throttle slightly, the recirc valve or blow off valve bleeds pressure back to the intake or in the case of a blow off valve, the atmosphere. If this pressure is not released properly, it gets released through the air filter.

3) Boost solenoid with no control unit ---- hrmm dangerous dude no control ---- could also cause that fluttering noise--- get it fixed dude


Get the temp issue fixed:
1) You've either got a bad water pump that doesnt spin nicely at low revs and spins up faster at high revs to cool the water down through the radiator or,

2) You've got a blocked radiator or,

3) You've got a bad thermostat or,

4) Maybe faulty temp gauge but i seriously doubt it.

Get it fixed before you blow a headgasket n damage the heads. Expensiveeeee.

ASG will be up to it I'm sure.

My 2 cents, hope it helps you out.

Regards,
Mao

Thanks RoughStilin ur a legend, but dw about it for now I'm gona get asg to take a look.. when i get money that is >< man i hate exams... not enough time 2 work.

Mao.. Thanks 4 all the help man ill def keep all that stuff in mind! and if i am gettin rid of those cables ill let ya kno 4 sure.

(sorry took so long 2 reply.. got exams atm)

No worries man. The offer still stands, so if you do need a hand, just send me through a PM. I work away though, so it might be a week or so from when you send the PM to me being available.

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Cheers,

Simon.