sti_rye84

I HAVE A 2.0 STI V8 2003 FULL DE CAT AND COLD AIR INDUCTION 3PORT BOOST SELINOID 255 WALBRO AND A MAP HAPPY DAYS UNTILL OTHER DAY LOSS OF POWER ON BOOST LIKE A FLAT SPOT OR BOOST DROP MID RANGE SO I HAVE BOUGHT A BOOST GAUGE AND CHANGED ACTUATOR NOTHING STILL SAME NO POWER AND BANGING AND BACKFIREING WHATS WRONG

craigybaby

iTrader: (8)

could be a maf sensor i had one go down on mine and boost dropped loads seem to missfire and kangaroo and have a flat spot

Glowplug

iTrader: (8)

There is a button called 'Caps Lock', you know what to do...

Got to get it on the diagnostics really mate. You could chuck cash at all sorts of sensors and still be no further on.

GezP

iTrader: (23)

I'm no mechanic but there are a few things I've learnt as I've had a similar issue.

Firstly check all pipes around turbo, intercooler etc

Get yourself a can of brake cleaner:

Clean the MAF sensor
Clean the boost solenoid

Check your spark plugs. This is where my problem was. My scooby has been modded a little but still had standard spark plugs. The spark gap in mine were massive. I replaced them with 7's and worked a treat.

Also: one other guy on here mentioned about the turbo housing be cracked. Is it caining juice? if not it wont be this

When I had my boost problem, no engine management light came up and the mechanic could find any faults through his laptop. Maybe try these few simple things, it could save you some money in the long run

good luck

wrx fifer

iTrader: (34)

as above all boost/air pipes/intercooler etc check for splits/ any off around all hose clips etc.
good starting point at least rules it out if nothing else

EngineMapper @ Group B Motorsport

Does sound a lot like a boost leak has appeared, very common if you've upped the demand from the turbo, definately check all of the above and getting a boost gauge is a good place to start.

I know you're a little distance away from me, but I'd be happy to look at diagnose and advise if necesary.

Graham

Mattes21

Hi, Guys...
Newbe here.. I have some questions!
I have a Impreza GB270 2.5L 2007/57 Mileage @18,000
Heres my problem, Yesterday I noticed that (what seems like) Boost loss!
It just doesn't seem to take off like it used to, I haven't done anything differently and the car isn't due a service. It definately seems like the turbo doesn't seem to be spooling up like it was. However high end of the revs its perfectly fine...
any ideas? I have checked all turbo pipes etc

GezP

iTrader: (23)

I had the exact same problem, boost problems low but fine top end. After a bit of detective work I found out it was the spark plugs. The gap within the spark plug was massive way more than double it should of been.

Defo worth checking mate

Mattes21

Hi, Thanks for the reply!
It had we worried because I have done some forum research and have read nothing but people complaining about the reliability of the uk 2.5 litre engine...
My dad (AA mechanic) seemed to think spark plugs, But once again (forum reading) dirty boost sensor? or something? lol
Ive already checked and cleaned the maf sensor.

It just doesnt feel right... My princess is poorly lol

Just out of interest what plugs did you fit? Standard? double core or those triple spark ones?

If I am to replace the plugs whilst dismantling half the engine bay to do it.. lol
is there anything I can tinker with to create boost/ BHP? tips or tricks?

GezP

iTrader: (23)

don't worry about the block, I've heard nothing but good things about them and also the 2.5 engine I've been told is a lot easier to tune and get better figures than the 2.0.

I've heard horror stories about people being charged stupid money for mechanics changing spark plugs - heard one story of a garage charging the bloke for the engine to be lifted to get to access to the spark plugs.

I had a mechanic Tim - Subbus (who I highly recommend) come round to diagnose and sort the problem. It took him 30-45 mins to do all four. All you need to do is remove the air box (if still running standard air-box) and the battery on the other side. Its a bit fiddly but a pro shouldn't have a problem. Your dad should **** it mate.

Sorry not sure the exact plugs used, all I know is they were NGK long plugs.

In terms of boost mate - get an expert !!!!! I would recommend Duncan (racedynamix) he knows what he's doing and can give you proper advice. My tip would be, get yourself a tuner/mapper and go by what he say's

hope this helps mate

Mattes21

Yeah mate your information helps me greatly!
I should be grateful for the 266bhp standard shouldn't I...
However it might just be me, but it seems as if my body has adjusted to the BHP and it simply doesn't seem quick lol if that makes sense...

I'll pop to my loacal car spares or halfords today and have a gander at the plugs... Defo worth doing if not to try and solve the problem!

The only thing I have done to it is fit a Bailey DV12 dump valve.
Don't want to pee you off dude by asking all sorts of questions, so tell me to do 1 if you like... lol
What do you think of dump valves? are they worth it? or should I stick with the standard Re circ valve?

once again thanks in advance!
matt

GezP

iTrader: (23)

no worries mate, there's sod all on TV. people have helped me out in the past

"it simply doesn't seem quick" welcome to the tuning bug. when i first got my standard 06 wrx scooby I thought that was enough - didn't last long. Soon as I started speaking to Duncan and found out what I can do, my bank balance got a pounding (but its worth every penny though mate).

remember mate you have a scooby not a ford or vauxhall - halfords might not be your best place and what ever you do, do NOT listen to the spotty teenager about what spark plug to use, he probably has a push bike round the back and dreams about a badboy corsa. Call experts mate, try Tim and scoobyparts or scoobyworld. These people deal with scoobys all day every day.

Actually, thinking about it Mark at Lateral Performance could also help you - he's been really helpful to me in the past. Just google these names mate and they will come up and they deal with newbies all the time - I'm still a novice mate

Dump valves - funny one, I've heard so many stories about them. 90% say take them off. Also bailey is the cheapest make out there. You get what you pay for. I've just had to buy one due to fitting a front mount intercooler and I was told Turbosmart all the way. Even the expensive HKS has been known to stick and cause problems.

My best advice would be - only buy things for scooby people (or proper race people) as you will need help (as I do). Don't go cheap, you will be disappointed. Call a tuner/mapper and go with there recommendations - see him as your car's oracle.

It might cost mate but that love you have for your car will only get bigger and bigger

Mattes21

Aha it's clear to see you've had the same past experience of halfords as me then... Lol
I've been looking for the spark plugs on the internet all night, I've found the makes and model numbers I'm looking for, so I'll just have a look for myself! That way I can leave the spotty teenager to dream about his 3 cylinder 1.2 corsa sxi lol
I was thinking about taking the dump off to be fair, I just know I'll miss scaring kids on the way from work with it... As it dumps and they jump into Mommys arms cry lol yes... I'm sad hehe!
I don't want to tinker to much really, possibly look at a remap in the future... K&N panel filter or ram air induction some decent plugs and tlc!!
It's pretty smart interior wise with the clarion double din DVD/ sat nav!

Aha tell a lie I do want the bonnet and or roof vinyl wrapped... Thinking satin or matte black, what ya think? And any ideas on who or where to ask...

GezP

iTrader: (23)

I think we're in agreement that halfords is good for copper slip and car shampoo!

Has the car had a remap? if so, with the dump valve?

A dump valve does a lot more than just make a cool sound (which I do like too). If the car doesn't know its got a dump valve (because it's not been remapped) take it off straight away and put the standard one back)

If the car has been remapped and knows its got a dump valve - don't take it off. You can unbalance it all and cause more problems.

If you're gonna keep it - just get a better quality one when you can.

My first stage of the tunning bug was:

Afterburner - backbox, center section and de-cat downpipe
cosworth panel filter
And a remap by duncan

It went up to 275bhp ish and it was a different car.

Dont worry about induction kits etc until a lot later and you want much more power.

Personally, wrapped bonnets etc aren't my thing. Totally understand why people do it. My moto is - if its not real don't do it. I would prefer to buy a £20 topman shirt than a £20 fake prada shirt (really hope that doesn't offend anyone).

dynamix

iTrader: (3)

Baileys ... ahh !

Almost always the cause of proiblems. Refit the original dump valve and see if the problem goes away, then chuck the baileys in the bin

Mattes21

Ha ha... Took it straight off!
It turns out I've actually destroyed it... Possibly to much pressure?!
Either way I have re fitted the re-circ valve tonight when I got back from work, will find out results when I go back to work today!
Day of Sunday so the plugs will be sorted then... Hopefully it's just a straight forward issue in terms of the boost loss!

On brighter news a pal of my old mans said he would remap it for me...fingers crossed on that one!

Buy cheers for all your help guys, it's been very helpful, Matt!

dynamix

iTrader: (3)

I am sure that will have sorted it or at the very least improved it massively

Glowplug

iTrader: (8)

I'll cross mine for you too!!

Mattes21

And toes? Lol
Yeah improved greatly on the way to work...
Still not it's usual self though! I'm going to agree with it being the plugs... You can almost feel it miss a beat when sat in traffic! Very mildly, but it's there!

It's been great to get so much advise though,
So thank you for that!
Matt

GezP

iTrader: (23)

glad its getting better mate and hopefully the spark plugs will really help too.

Hope your dad's mate is an expert, let us know how you get on mate

Glowplug

iTrader: (8)

I was actually referring to the 'mates old man doing the remap'. No offense as i don't know the old man in question but it's not the simplest job on the sheet.

KAS35RSTI

iTrader: (73)

I will get my entire family to cross there fingers on behalf of you!

Mattes21

It's a professional shop! My dad being a mechanic... Has know this bloke for years!
He said he would to it as a foreigner, I.e. Cash in hand...
To which I'm not going to complain as it's cheap! Lol
I'll just be glad to to get I on the rolling road to see what she can do...

Mattes21

Plugs changed today! It's like a whole new car! Platinium plugs...

GezP

iTrader: (23)

glad to hear it mate