i have a 1994 import impreza wrx sti and have a odd boosting issue when you put your foot flat down it boost straight up to 1.1 bar of boost and its fine in 1st gear but though the other gears it reaches the same bar of boost and very quickly then it pops and go's as if it was over boosting but i have the stantard boost solinoid on it this has been happening for awhile now i have tried everything i can think of iv changed the crack sensor and 02sensor the dump vavle the fuel reg the pencil coils and put new spark plugs in it and changed the exhaust system on the off chance it was the cat blocked up iv checked all the boost pipes and they seem fine also changed the actuater but still got the issue and is really starting to **** me off now!!! so if anyone could help that would be great thanks shaun

 

if you are getting 1.1 bar in first then it sounds like the boost is set too high. you should only really achive your max boost target in 4th and 5th where there is more load on the engine,
The only way you could have the boost too high with the standard solenoid is if the restrictor pill has been removed from the bottom pipe on the solenoid.
Has anyone fitted aftermarket hoses?

 

not got an eclispe chip has it on a serious note try and adjust the actuator arm to open the wastegate a little more and lower the total boost, sounds like your flying past the boost target and hitting fuel cut, just noticed there is not mention of cleaning the boost solenoid, i would try that first if i were you.

 

hi mate yea i for that to iv changed and checked the actuater and its set so on tick over the wastgate is closed fully is this rite? and yes thats in there but ill check and see weather its on the rite place and yes they have fitted after market hoses was done before i got the car but the other thing that is bugging me is the 1st engine init went bang so got anouther one the same and had it fitted but it was out of a wrx sti automatic would that cause any issue? and it does have a frount mount intercooler and p1 drifter. i have changed it with one out of another scoob that was running perfect before i removed it so :/ so any other advise or help would good cheers lads

 

just had a look and it has a aftermarket pipe on it but and mate of mine has the same car and his has one on there too and his runs fine could it be something to do with the adjustment on the actuater as iut was out of a auto with stantard intercooler but mine has a front mount and is a manaul??? cheers

 

if it has aftermarket hoses on the soleniod then there is a good chance they have binned the restrictor in the bottom pipe by mistake. have you checked the bottom hose for the restrictor? it MUST be there for the boost control to work properly, hence your overboost. if your overboosting all the time its no wonder two engines have gone bang.

 

hello mate yes i have checked it and there is no restrictor in the pipe so could that be my problem? also the 1st engine had these after market pipes on it too but didnt have this problem untill 6months of driving it and then yea it went bang so if i get this rictrictor pipe and chuck it on the car should that solve my problems?

 

well if you are running the stock boost control system, i,e no bleed valve then i cant see how its gonna work properly without one! for the sake of a couple quid i would fit one back in and see how it runs.
check what ecu is fitted and open it up to see if its been chipped. we can then give you an idea of what boost you SHOULD be seeing.

 

Ok mate cheers for that I shell get one and see wot happens but wot I have boiled it down to is I put the actuator pipe and turbo pipe together so it blanks off the stock boost control unit and it hits about 0.6 max in 1st and 0.7 max in 4th and 5th so I think as you said it's got to be that resrector pill pipe or one of the other units other than the boost soilnoid would you agree with this mate? And I'll check the ecu later also

 

Tried that rectrictor pill pipe and no luck I still have the same issue so running out if things to try now so may have to taKe it to RPE and get them to plug it in and see wot I get from that hopefully itle be something silly

 

so you have the restrictor pill in the bottom hose?, what size did you fit? 2mm?
have you go the other two hoses the right way round? bottom one goes to actuator, top one to turbo outlet.
https://www.scoobynet.com/scoobynet-...or-3-port.html
what ecu is fitted? is it chipped?

 

Yep I have mate and the pipes are all round the rite way also and it's fitted with a SA unit the numbers on it read so255 00070
A18-0000 RZO
4210 and that's all it got on it is that any help?

 

Dj219957 is there any chance I could get your number and have a chat about it over the phone mate as this problem is starting to become a very big headache

 

2 ports boost solonoid has 2mm boost pill 3port has 1mm pill . when chipped with decat front mount etc it will sometimes still overboost , if it does use a 0.8mm welding tip

 

Problem solved put a 1.2 mig welder tip in the botem Pipe of the solenoid to the afm unit and works a treat getting around the 1bar mark maybe a lil over with no Over boost issues thanks guys for all your help may try a 1.5 and 1.8 mig welding tip too to see if I can get a lil extra out of the old girl haha

 

;-)