Hi all,
New to the forum and new to Subaru’s. I feel I should give as much info on my car as I’ve had minimal guidance to this point and would really appreciate any advice on anything I’ve done up to now. (warning this is long but I hope mildly interesting)

So I had a 96 1.5 manual wagon for 2 years just cos I needed a car and it was tidy at the time, that was stolen and destroyed 6 months ago and instead of being sensible and getting a car that’s hard to steal I bought a 96 wrx wagon cos I liked the practical boot space for bikes and thought 4wd and turbo would be very enjoyable on some Nz roads! It was not happy when I bought it but I thought I could fix it up. Fitted an alarm and tracker with remote fuel cut first off.

It had a leaking pipe from intercooler to turbo, still has turbo back 3” maybe 3.5 it’s silly big for a stock car I think.
Had a boost tap now back on factory solenoid (after much cleaning) does 10psi
Had a pod filter, now has stock air box (hard to find), I “cleaned” maf with maf cleaner..
Did timing belt. (Was a lil out)
Fell out of 5th took gearbox apart tightened nut restaked. Kept oil deflector thing cos it wasn’t completely destroyed.. found many teeth and chunks of metal. Cleaned and refilled with redline shockproof, and shift carefully. Also looked at turbo at this time had some shaft play but I dunno what’s normal. Very little oil in intercooler by the way..
Put in an innovate afr gauge. With sensor fitted towards the bottom of the down pipe.
cheap electronic oil pressure which goes up and down because of other current drawing sources, see around 80psi cold 60 hot on load and 10 at hot idle.. is this an issue? Could it need checking against a mechanical oil pressure gauge..
changed plugs, looked normal.
put walbro fuel pump in.( Probably pointless)
Oil after 3000km was very runny possibly gas in it?
leading into my main question among many, it has a tendency to go very lean on warm up up to 18-20kn the aft then cough pop and back to normalish, if I blip the throttle it will cut through it and run normal. When it’s hot it seems fine now, had some instances of doing it on the highway but that was with the pod. It also runs fat a lot of the time like 11.1 but will spend 20-30% of its cruising time at 13-14. Sometimes it idles bang on 14.7.1 but most of the time is on 11-12 can dip to 9 sometimes. At full load it’s good like 12s and whatever but I’m chasing optimal performance and don’t laugh too hard, gas mileage.. Would this behaviour indicate Maf sensor? Or o2 sensor, its possible the one that’s in there isn’t factory as it’s an aftermarket exhaust. Likewise for the maf think it has a green sticker on it.
Havent looked at the ecu yet might have a chip or something. Just would really appreciate some guidance from here. Should I buy a link ecu and try to learn that and perhaps tune it better? or is the stock ecu fine but being freaked out by something I or someone else before me has done like winding the clock back 6000km and trying to fix boost leaks with parcel tape, i sh$t you not.

Sorry this got so long winded any advice and or criticism would be appreciated.. cheers nick

would want to assume it’s standard as the car makes factory boost, has factory rev limit and speed cut.
Have been leaning towards the maf dieing after reading some more posts. It was banging around with the pod on before..

Finally had a chance to play with the car again. I’ve checked the ecu and I was not the first person there as I should probably expect. Looked standard but the plugs looked like they’d been out before, i I’ll post photos hopefully someone might know if it’s correct for the car. Put another green label maf on it. Problem I have is when the cars all warmed up driving in low rpms like 90% of driving the afr keeps going really high and the car splutters a bit, but if you apply more gas it surges/shudders out of it and holds 10-11 afr at wot and drives well but it’s awful to drive around normally. I’m now thinking o2 sensors? There pricy and probably rusted in quite well so don’t wanna miss something else it could be. Again any input would be much appreciated!

Sorry it’s upside down

Thanks for the quick replys. I will try disconnecting both o2 sensors? Is it more likely the front or rear one or impossible to know? Have a cheapie blue racetech or something bov that came with car, have new intercooler hoses and stuff so don’t think I have vacuume leak issues, sprayed around the pipes with wd40 and silicone spray and engine continued to idle smoothly.

I don’t have a chance to work on the car again for a few days as work trip is taking over. Just wanted to add in the meantime if it helps any diagnosis I have a bov like this one I’ll attach a picture of, also as alcazar asked I put in a new walbro fuel pump a few thousand km ago could this be my problem? Too much fuel pressure or something?

Ok will try and get hold of one thanks

Have just been for a drive with the front o2 sensor disconnected and it was much better only spiked lean unexpectedly once. Plugged it back in and with in minutes had it going lean again, unplugged and better again. I guess that means o2 is cooked? Also noticed a bit more lumpy idle and sometimes high idle. Didn’t get check engine light tho. Car was mostly in 14s range afr wise when cruising.