[Please explain how this CVT trans thingy works...]

Given that F1 banned them as soon as a team came remotely close to having a race-worthy one, they probably work a bit better than people give them credit for.

[Factory spark plugs for 2001 jdm v7 sti]

PFR6B according to NGK.

[Tyre recommendations - Best value performance compromise 2015 edition]

Dairusire was after 225/40R18 RS3s a while ago but our Hankook supplier wanted $999 per tyre so he noped out.

We're waiting for the Ventus V12 Evo 2 (K120) to come in to put on his car. Supplier says they don't know when it's meant to be coming in, but they've been available in the US for a couple of months.

[MAF reading 5v at idle?]

I didn't test the sensor directly, that's the MAF voltage reported by the ECU.

Both MAFs cause the car to sputter and die if plugged in, but I need some way of proving the MAF is ****ed and the car is otherwise fine because supplier claims it was good.

Easiest way is to find another GC8 WRX and swap test it, I guess.

[MAF reading 5v at idle?]

As above. I will readily admit to not being a proficient automotive electrician.

Dairusire's GC8 Type RA has a faulty MAF so we bought a replacement. No dice - CEL still lit (have tried resetting via OBD, instant MAF DTC when the engine fires up.) What confuses me, though, is that according to the ECU the replacement MAF reads ~5v when idling. Part supplier insists that the replacement MAF is known good and doesn't want to send another without further investigation.

Is there any sort of electrical fault (ECU?) that can cause a 5v MAF output at idle, or are they having me on and sent me a dead sensor?

EDIT: "approximately 5v" and not "negative 5v". Font be weird.

[What have you done to your car today?]

Attempted to repair Dairusire's Type RA (again).

tl;dr MAF is shot, suspect replacement MAF is also shot but can't prove it to part supplier without third MAF or second WRX STi.

[grinding/screeching sound when cold start]

Would suspect worn rather than loose belts.

If the squealing is extremely loud when at full lock then almost certainly PS belt.

[Poll : Tyres 2015 What are you running?]

Attempting to wear current Nankangs as rapidly as possible due to godawful howl at motorway speeds and miserable wet grip (I didn't pick them, dealer fitted a full set).

Will be switching to Hankook or Falken because employee discount.

[Tyre recommendations - Best value performance compromise 2015 edition]

Would recommend the Ventus V12 Evo (K110) over the S1 Evo2 for performance applications, very good performance for what you pay.

With that said, a taxi I fitted S1 Evo 2s to ran 80k on the rears. Driver was very satisfied with the performance and (lack of) road noise. Fronts are still going so we will have to see how they do.

[Takata airbags recall]

Just checked the NZTA Safety Recalls Database.

2003 JDM Legacies were recalled in February this year for airbag-related issues (possibly unrelated to the Takata recall). Otherwise nothing yet.

[Please explain how this CVT trans thingy works...]

I also dislike normal autos, although in my case it's because I hate the transmission hunting for ratios when driving in hilly areas (see: half of New Zealand).

The best explanation I can give you is that the Subaru CVT is somewhere between an automatic transmission and a DSG if you're shifting manually. It's pretty obvious that it's pretending to be a manual - slight lag, ratios are a bit funky (6th is incredibly long), doesn't like rapid downshifting - but otherwise it's not bad. Feels better than a normal automatic.

I leave it in automatic most of the time, though. It does a pretty good job of being in the right ratio.

[CVT Trans service]

According to owner's manual the CVT never requires servicing, which I take with a large pinch of salt.

As far as Auckland goes try Kaspa Transmissions. I have no idea if they do the Subaru CVTs specifically, but they definitely have CVT experience.

[Please explain how this CVT trans thingy works...]

Hello, fellow BR9 CVT owner.

1) No, you can hold the car in place with the accelerator if you want to, although the owner's manual probably recommends against this somewhere. This has more to do with the torque converter than the CVT itself - note that the CVT also has a much weaker "creep" (rolling forward when idling in gear) than a car with a traditional automatic. As far as I'm aware, this is because the Subie CVT has a torque converter lockup clutch. Therefore the torque converter is only needed for starting off, after which point the fluid coupling locks and the CVT input is directly connected to the crankshaft.

2) Again, lockup clutch. Since the CVT is mechanically connected to the crankshaft it engine brakes. Particularly noticeable if you shift the CVT manually.

Disclaimer: I don't know the specifics of the BR9 CVT as I've never serviced, replaced, or dismantled one.