EvilBevel

Still sounds like overboost to me.

Cleaning out the pipework (not the wastegate) is one thing, cleaning the boost solenoid is another one.

I don't remember the correct procedure, you you should basically make sure the boost solenoid is cycling, then feed in some cleaner, and than blow on the pipe to the solenoid to make sure it goes through it.

1.1 bar is exactly where you (in this cold weather) would expect fuel cuts on a <MY99

MAFFA

Thanks mate,

I've cleaned out all the pipework around the wastegate. Which is the Boost solenoid??

I hope i'm not confusing the two. Is the wastegate the silver coloured thing in the front of the wheel arch on the drivers side in the engine bay? It's got three pipes coming out of it, one of which goes to that other silver coloured thing in front of the turbo (Very technical I know!!!)

MAFFA

EvilBevel

That's the boost solenoid alright.

The wastegate is an integral part of your turbo, and if you look down your engine bay, you can see the wastegate button just next (left from your POV) to your turbo, surrounded by the heat shield The black pipes come out of the inlet (turbo to intercooler) and then (depending on your MY) goes to the boost solenoid and then back to the wastegate button.

So it does sound like you did OK, but IIRC you need to connect two connectors (green & black ? I never did this) under your steering wheel to make the boost solenoid "work" whilst cleaning.

Another problem could be the MAF sensor, but I still suspect (I'm not an expert) overboost.

Theo

MAFFA

Yep I connected the connectors under the steering wheel to make the Solenoid pulsate. Can the wastegate be cleaned then? Is this the thing that looks like an overgrown silver lolly sticking out from the Turbo?

Mmmm MAF Sensor. Can this be cleaned?

If it is overboost how can you correct it?

Sorry for so many questions but i'd rather do the job myself than pay somebody to do it. I'm not a mechanic but if someone tells me how to do something I can 99% of the time just get on with it.

MAFFA

MAFFA

Yep i'm a muppet too nowadays

sammyh

iTrader: (1)

I agree Maffa you are a muppet speak to Steve Lawson he'll fix your car because he knows everything and he is not to far from you I think, i'll mail you his number.

Sam

john banks

If it is overboosting (do you have a boost gauge, but as stated 1.1bar is too high) then it has happened because of your downpipe if all the solenoid pipework is cleaned. It is quite common after breathing mods in cold weather.

You do not need a remap to sort this. You need to change the size of the tiny restrictor that sits in the pipe that comes off the outlet pipe after the turbo and heads towards a T-piece and then the wastegate actuator (shiny cylinder near the lollypop kind of area).

If it is like later cars you need to very slightly enlarge the size of this hole (say from 1.2 to 1.3mm) and this should fix your overboost. It is easy to go too far with it. You might want to fit a needle valve instead of a restrictor to adjust it precisely - look back over the last few months of Drivetrain and you will see loads of threads on this.

MAFFA

Thanks guys.

I didn't actually mean that I ragged my car when cold. I meant when it had warmed up (say after 10 mins driving). The problem occurs when the car has been driven over a distance & the engine & exhaust are really hot.

MAFFA

Bitten Hero

My mistake

John's right about the 'wastegate pipe orifice' (I believe the Subaru term for it is ) . I've heard of changing it fixing the overboost problems, particularly on older STi's. Any Subaru dealership can get hold of one for you, for 0.8mm, 1.0mm and 1.2mm. Not sure which one you need (sorry!) but the dealership should be able to find out.

John, you are rapidly turning into a boost guru... be careful!

Cheers
Richard

john banks

Subaru just drill them out with 0.1mm increment drills. You can buy a set from Maplin for about £5. Better buy a valve though otherwise if you are like me you will always be drilling and resoldering to get it right and if you get it optimum on a warm day it will overboost on a cold day. See my thread in drivetrain about 6 weeks ago.

john banks

http://www.scoobynet.co.uk/bbs/threa...threadid=56487

http://www.scoobynet.co.uk/bbs/threa...threadid=60659

Bitten Hero

UK MY95 - see the original post

Richard

john banks

Well I say find a restrictor and replace it with a valve. You will find out soon enough whether you need to be smaller or larger. Go easy with the throttle at spool up and you will know if it will hit 7 or 27PSI.

john banks

It might cure it but you end up with lower boost. If that is the case you need finer adjustment - ie a needle valve as described in the thread I linked to above.

MAFFA

Where can I get one of those from?

MAFFA

john banks

Read the fourth posting in the first thread I posted

MAFFA

Now you've majorly lost me????

After looking around the net i'm guessing you mean something like a boost control valve that you can get for about £15-£20?

Bob Rawle

On a MY95 the restrictor is in a totally different place and has a totally different function, if you find it and open it up then you will increase the overboost you are suffering not decrease it, there are several different setups dependant on model and model year of car.

Your car has a 2.0mm restrictor fitted into the pipe that exits the bottom of the solenoid, pull the pipe off the solenoid and check, it may heve been removed, if so thats your problem. Go to your dealer and get it replaced, this will solve the problem. If its there you need to reduce the size of the restrictor hole to lower overboost.

Good illustration of good intentions potentially causing a worse situation, always qualify advice with car model and year so at least the recipient has a chance of deciding whether it is relevamnt or not. Not a dig at anyone, just a concern.

cheers

MAFFA

Cheers guys Although all this pipework has completely lost me but i'll work it out i'm sure.

Thanks again

MAFFA

Bitten Hero

Thanks Bob - sound advice. We did all say that our experience was for later cars though but you're absolutely right that at the end of the day it's best to check with the dealer or someone who knows, like yourself.

Good luck sorting it out...

Cheers
Richard

john banks

Trouble is who to trust? In my experience SOME dealers talk more rubbish than most folk on here. Like telling me to run my new PPP on UL rather than SUL to cure overboost! Only when I insisted something was done were restrictors changed.

Bitten Hero

Very good point. A couple of times I've ended up telling the dealer about how things work or what the effect of things is. Generally I think the serious tuners and developers of kit for the Scoobies are probably the most clued up (Bob Rawle, Pete Croney, etc etc). But then what do I know?

Richard

EvilBevel

Pfew, for once my memory didn't totally betray me

Bob is right or course, and I think the confusion sometimes has to do with the format of a bbs ... We all read different posts, sometimes the same, and we assume that our last post on a different thread has been read by all.

In one of the many Dawes threads I actually warned about the different MY's having a very different setup (boost control, injectors, ECU, etc).

Roughly though (very roughly) you could say that the MY99/00 are virtually the same, as are the MY97/98 and the MY95/96. Amongst them, there are *large* differences (TD05 vs TD04 for example) The MY01 is again a totally different animal altogether.

We could do with a FAQ about these "standard" problems (per MY), with detailed explanations of what happens and how to cure it. Pictures would be a good thing as well. Such a FAQ would ideally be "endorsed" or at least proofread by people in the know such as Bob. It should also contain a thousand warnings & disclaimers left & right.

Still, even that wouldn't prevent people from drawing the wrong conclusions... sometimes your problem may resembe another one, but is in fact totally different. It's a bit like giving free medical advice over the internet without actually checking the patient "hands on".

I would always advice - even if it costs money - to have the problem checked by someone you trust, someone who knows what they are doing. Yes, it can help to ask on here what it might be (or look it up in said "faq"), so you have a headstart, but fiddling yourself on the basis of free advice without actually knowing what you are doing is not recommandable. The road to hell is indeed paved with good intentions.

Maybe we should at least agree that every post we make (question or answer) is fully qualified with the MY, as Bob suggests.

Theo

EvilBevel

A few other thoughts popped to mind: even specifically quoting the MY may not be enough ... you may have bought your car end 1998 (making it a MY99) or Jan 2001 (and it would still be the old model MY00) And if you're from the states, you would have to add 1 (as they are calling the WRX MY02.

And also STi vs UK scoob would be another big item in what advice to give ... I just read in another thread that someone was adviced to have an equal length header on his P1 "as it would give 25 bhp extra" ... can you say "lean as fvuck" ?

john banks

All very true Theo. Things that sound like overboost seem endemic at this time of year.

Who has the time to write such a FAQ? I don't and am not qualified to do so. Anyone that is is probably too busy because they do it professionally? The SIDC FAQ is a case in point that is has quickly become dramatically out of date and no one seems to have the time to update it? Or am I wrong?

A sticky thread could be a shortcut, as time again the same questions are asked in Drivetrain and other forums - eg. ICE and time and again people waste time trotting out the same old answers me included.

Bitten Hero

I've often thought that would be a good idea - a few threads dated 2100 like in the Was it you? forum, that have a FAQ in. These could start with a summary of what the thread is about, and then people could reply with their comments. Ideally these would then be merged into the first posting, as otherwise you'd end up with loads of pages to look at. However this almost puts us back to square one in terms of maintaining it, but it would at least distribute the load across the moderators.

Cheers
Richard

MAFFA

Well looks like people have been busy on my thread coming up with some good ideas I hope. Haven't had a chance to look for the restrictor yet as I leave for work in the dark & come home in the dark (no garage) but I will at the weekend or maybe if I get a lunch break!!!!!!!!

Anyway thanks for all the help - Much appreciated

MAFFA

Bitten Hero

No problem mate Let us know how you get on.

Cheers
Richard

ptholt

just give steve lawson a call and get it booked in maffa

Bob Rawle

Hey John no problem,

The boost control configurations are very confusing, UK cars are slightly more consistent than jap spec.

UK cars

Up to MY96 three port solenoid was used, restrictor in the vent pipe (lower port).

MY97-98 two port solenoid of similar design to three port, with tee piece and restrictor between turbo/actuator.

MY99-00 two port of different design with tee piece and restrictor as before.

MY01- two port system again

The different two port solenoid fitted to the MY99-00 copes with constant pulsing better, earlier types can be prone to "hanging" on the bemf if pulsed too fast for too long.

Jap spec, same as UK except that the STi 3 uses a two port and the STi 4 uses a three port, don't ask why, 22B also uses a three port. Sti 5/6 same as UK, Sti 1 and 2 same as UK.

The three port provides for a "tighter" more finite control as it releases "slugs" of pressure from the actuator instead of a bleed of air, being three port as it opens one it closes off the other, the two port system continually bleeds some air from the turbo, three port closes off this outlet when releasing air from the actuator. Be careful, if you fit a three port to a UK car instead of a two port then the restrictor also needs to be moved into the vent pipe otherwise you will get kangaroo boost. This was/is a Subaru "fix" for overboost type problems, the cheaper route of drilling out restrictors seems to be more normal these days though.

cheers