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Old 24 September 2006, 09:13 PM
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moneys
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Default Fluctuating boost

Hi i have a bugeye wrx the only mods i have is a de-cat down pipe. I first noticed this problem a few weeks ago and its annoying me a lot now. When i drive hard through 3rd 4th and 5th my boost go,s up to .9 bar but then will fluctuate between .9 and .6 whilst being pushed, you can actually feel the turbo boosting and then letting off and then boosting again its not violent but quite smooth . I cleaned the boost control the other week and it seemed to go away but the car was left idle over last weekend (5 days in total) and it now seems to be back and annoying the hell out of me. If its the boost control how much will one set me back about ? if not this any other ideas will be greatly appreciated
thanks for looking ste
Old 25 September 2006, 06:31 PM
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anyone???????????????????????????????????
Old 25 September 2006, 07:26 PM
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Mines the same at the moment mate.

Got some uprated spark plugs to go in (due anyway as the car needs it 30k service) but 3 port boost solenoid also being fitted prior to a remap.

cost is approx 150 plus vat although I suspect you can get these cheaper (even seen them on ebay)
Old 26 September 2006, 05:55 PM
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just cleaned the solenoid and pipes and its still the same any idea,s on what to do now?
Old 26 September 2006, 07:22 PM
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gws73
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Have you tried resetting the ECU to see if any fault codes are displayed?
And have you actually cleaned the solenoid itself, not just the pipes?
Old 26 September 2006, 07:27 PM
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Scoobyfirsttime
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Does resetting your ECU mean you lose any remapping done ?
Old 26 September 2006, 07:44 PM
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Originally Posted by gws73
Have you tried resetting the ECU to see if any fault codes are displayed?
And have you actually cleaned the solenoid itself, not just the pipes?
no i thought it wasn,t possible to re-set the newage impreza,s or have a read this wrong somewhere? i,ve cleaned the solenoid and both pipe,s with brake cleaner
Old 26 September 2006, 10:12 PM
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would it be worth me just buying a new 2 port solenoid?
Old 27 September 2006, 10:41 AM
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Jolly Green Monster
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Originally Posted by Scoobyfirsttime
Does resetting your ECU mean you lose any remapping done ?
no
Old 27 September 2006, 03:29 PM
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KenS55STI
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Your decat downpipe will be causing the car to overboost and the ecu will be constantly trying to correct it and causing the fluctuations. Solutions are:

Refit original downpipe
Change restrictor in boost pipe to reduce overall boost
Have the boost control maps adjusted to stop the overboost, this will require a remap.

Do not fit a 3 port solenoid or it will make the overboost worse.
Old 27 September 2006, 08:53 PM
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I had the same prob i got a new 3 port sold second hand it fix prob then came back again what i did was put a bleed valve on mine and it bypass the probs.

Hope that helps
Old 27 September 2006, 10:10 PM
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moneys
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Originally Posted by scooby25
I had the same prob i got a new 3 port sold second hand it fix prob then came back again what i did was put a bleed valve on mine and it bypass the probs.

Hope that helps
hello mate the thing is i,ve still got the standard 2 port valve so i,m toying with the idea of changing this first as i,d imagine it will be the cheapest option
Old 27 September 2006, 10:35 PM
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Bob Rawle
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"Do not fit a 3 port solenoid or it will make the overboost worse"

Uum ... nope it won't if its plumbed in properly, will actualy reduce boost a tad.

As I state though it has to be plumbed in correctly. Most people don't appreciate what works and what causes issues in that respect.

Problem is a boost control dynamics issue relating to the down pipe, you could try restricting the vent pipe ( from solenoid back to air intake) with a 1.2mm restictor, that should damp it.

A remap would/should fix it completely but if you don't want its expensive as a fix.

A bleed valve bypasses the problem and the ecu's safety features !!!

cheers

bob
Old 27 September 2006, 10:42 PM
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moneys
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Originally Posted by Bob Rawle
"Do not fit a 3 port solenoid or it will make the overboost worse"

Uum ... nope it won't if its plumbed in properly, will actualy reduce boost a tad.

As I state though it has to be plumbed in correctly. Most people don't appreciate what works and what causes issues in that respect.

Problem is a boost control dynamics issue relating to the down pipe, you could try restricting the vent pipe ( from solenoid back to air intake) with a 1.2mm restictor, that should damp it.

A remap would/should fix it completely but if you don't want its expensive as a fix.

A bleed valve bypasses the problem and the ecu's safety features !!!

cheers

bob
i,ve read up a bit on the 3 port solenoids on here and apparently you need to have a re-map to fit one of these and i just dont have the funds for that sort of fix at the moment. I,m currently on the lookout for a 2nd hand 2 port or i will phone up tomorrow and get a price on a new 2 port. if this doesnt fix it i just need to know what to do next?
ste
Old 28 September 2006, 09:08 PM
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moneys
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thanks for everyone,s help so far and also the people that have p.m,d me hopefully i,ll have this sorted soon. spoke to pete at prosport today and he said that whilst the pipe,s are off the solenoid that you can connect 2 wire,s under the dash to make the solenoid pulse , this will shift any crap that may be stuck in there better than just spraying the brake fluid down it.
Old 28 September 2006, 10:05 PM
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gws73
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Spray brake cleaner directly into it whilst the solenoid is pulsing - this will well and truly clean all the cr*p out of it.

I had boost problems a while back, so fitted a manual boost controller - now set to 1.1bar. Best £20 I ever spent!

BTW - make sure you switch the ignition on to make the solenoid pulse.
Old 28 September 2006, 10:12 PM
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moneys
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pete said i could go down the garage and he would show me how to do it. thats why prosport has such a good rep the service is truly fantastic
Old 28 September 2006, 10:20 PM
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Fuzz
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No amount of cleaning will fix it IMO, as has been said already, it's caused by the free flowing downpipe you have fitted.

Listen to Bob, the cheap fix is a restrictor in what you have already got.



Andy
Old 28 September 2006, 10:41 PM
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Another way as suggested is a manual boost controller will help control things and let you have a bit more boost as well
Old 02 October 2006, 09:39 PM
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moneys
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The problem seems to of cleared up i,ve done nothing other than what i,ve said in this thread but as of friday the boostseems to be beck to normal i,ll keep an eye on it and let you know if the problem re-appears.
thanks for the help
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