Boost issues - BF5 GT

[Shale]

My Frankie is being retarded.

What I'm working with: It's running a ver2 WRX 20G motor with a TD05. Has a BG5 GT auto gearbox, RS-RA ECU. Other than that it's completely stock...factory boost control, etc.

The issue is that when I put down any substantial amount of throttle, you can hear the TD04 spooling away but nothing remarkable happens. It's sluggish as hell until it gets over 5000rpm, where it will start pulling simply because of the high revs. There's no sudden boost.

This started happening almost overnight one day, after boosting pretty hard considering what's under the bonnet.

My thoughts are:

- broken factory boost control, shat boost control solenoid?

- massive boost leak somewhere? Where I don't know.

- broken turbo? There was no play when I put it in. It's not particularly noisy, and never has been.

I should really install a boost gauge temporarily to see wtf it is doing, eh. (I'm a brand-whore, and want a Defi gauge...but can't afford yet). No point in me myself hunting for boost leaks, I wouldn't know my way around all of that crap if my life depended on it (shoosh, N/A driver...and learning slowly ).

Any other thoughts, anything I should check on?

Also, it's running brilliantly otherwise. No misfires, no shudders, no strange noises.

Edit: If the moment calls for it, I also have a spare VF10 which I KNOW does what it's told.

[Guest itsgotgo]

block the wastegate vac line and do a small boost,if it boosts then it is not the turbo.

[madmike]

You need to fit a boost gauge.....

That is going to tell you what's happening..

[Guest boostin]

 madmike said:

You need to fit a boost gauge.....

That is going to tell you what's happening..

Yup, gauge first. You can pick up Autogage boost gauges for about $30 these days.

[Shale]

Yah, will get something cheap and nasty in there asap.

Took her for a boost for the first time in a week, and the little sh!t has developed new symptoms. Boosts suddenly and strongly from 4k when cold (I know I know...the motor cost $500, I don't care), but once warm it gives me nothing down low and horribly lumpy hesitation above 3.5k. Misfires on first start-up as it always does, which is leading me to think the coils might have gotten worse. For that, I have that coilpack conversion... ;D

Yet on the last 2km from home, it would boost reliably from 3k PROVIDED I only used partial throttle.

*bashes face against keyboard*

[Guest boostin]

Air flow meter??

Just throwing it out there....

[Shale]

It's green... that rates pretty damn high up the list of possibilities

[wrx_lou]

 Shale said:

It's running a ver2 WRX 20G motor with a [glow=red,2,300]TD05[/glow]...........you can hear the [glow=red,2,300]TD04[/glow] spooling

[Guest boostin]

Yeah I spotted that too....

[Guest]

 Shale said:

Yah, will get something cheap and nasty in there asap.

Took her for a boost for the first time in a week, and the little sh!t has developed new symptoms. Boosts suddenly and strongly from 4k when cold (I know I know...the motor cost $500, I don't care), but once warm it gives me nothing down low and horribly lumpy hesitation above 3.5k. Misfires on first start-up as it always does, which is leading me to think the coils might have gotten worse. For that, I have that coilpack conversion... ;D

Yet on the last 2km from home, it would boost reliably from 3k PROVIDED I only used partial throttle.

*bashes face against keyboard*

you runing in Open-Loop mode or Closed-Loop mode on your ECU? if you know at all that is, just working on a Theory

[Bazza-NZ]

My BF5 did this a while again, replaced O2 sensor and went find again

my bet is either O2 sensor or AFM (Greens always break but plenty of them out there)

[Shale]

 wrx_lou']

[quote name='Shale said:

It's running a ver2 WRX 20G motor with a glow=red,2,300]TD05[/glow]...........you can hear the [glow=red,2,300]TD04[/glow] spooling

It's called typing on a Mac keyboard. One of the white things. They are loud, and my fingers fit in the key gaps. You're lucky it's not a TD54!

EGOREX: iunno, I'm not the one that shoved it in...lol.

I'm going to hazard a guess AFM also, at this point, but it IS behaving like it has a munted O2 in a way. Boosting fine when cold or on very partial throttle (it is changing day to day at the moment, wtf) but badly behaved when warm.

We've got a few spares, so it's time to rip out, check and diagnose ;D I want my freakin turbo back, the Impreza is faster at the moment!

[zarnah]

 Shale said:

(I know I know...the motor cost $500, I don't care),

problem found.....?

[Shale]

It is a warrantied and tested unit from one of the better Subaru wreckers, actually. It's far from a TM AWW BRU I FINK ITZ A SUBBI ENGINGE IT ALGUD motor

[Guest]

 zarnah']

[quote name='Shale said:

(I know I know...the motor cost $500, I don't care),

/quote]

problem found.....?

:D :D i was going to say the same thing but wanted to be nice, plus iv picked up some golden ones for that money, but some doggy ones to

[Shale]

Dodgy was what came out

Note that they normally sell the motor I got for $1050+GST I'm just very, very special.

[Guest Oscar]

Your car is broken. The best course of action is to give it to me.

[Shale]

F**k off Ric she's my baby ;D

Actually strange thing. Through no intervention of my own she started working again properly over the weekend. Boost when I wanted it, no hesitation, no misfire. I'm just waiting for it to start playing up again in a day or two

Bloody turbos!

[wildturkey]

 Shale said:

Yah, will get something cheap and nasty in there asap.

Took her for a boost for the first time in a week, and the little sh!t has developed new symptoms. Boosts suddenly and strongly from 4k when cold (I know I know...the motor cost $500, I don't care), but once warm it gives me nothing down low and horribly lumpy hesitation above 3.5k. Misfires on first start-up as it always does, which is leading me to think the coils might have gotten worse. For that, I have that coilpack conversion... ;D

Yet on the last 2km from home, it would boost reliably from 3k PROVIDED I only used partial throttle.

*bashes face against keyboard*

Hi what's ur coil pack conversion?

[Shale]

Wasted spark, because gen1 coils are epic fail (literally, they keep on failing!). These ones are ancient, and I am NOT replacing them all for $100 each