hey any help would be great as trying to sel my car, whats happening its just boosting to whatever i want until it cuts out with a big bang where its reached stupid boost pressure like 2 or 3 bar, its like my boost keeps adjusting itself but now where it use to reach 0.8 bar its like the restricor whatever stops the boost at 0.8 bar has gone and its just boosts to where i want?

any ideasss..?

 

Check the pipe going to your actuator, sounds like its split or come off. Also worth looking at the pipes going to your boost solanoid.

 

https://www.scoobynet.com/general-te...lp-advice.html

 

i have looked at all that and couldnt see any signs of fault there at all with the pipes.

 

its a 1995 wrx with full exhaust system with decat tdo5 turbo hks filter and thats about it , i had it checked by a subaru specialist and all he could find is the MAP sensor reading wrong so i replaced that and still got the problem havent taken it back to him as would like to solve my self if simple.

 

its a split vacuum , i think it will be from the solenoid to the turbo.

be careful if you let it overboost too many times its gonna go bang

 

Split or leaking pipe work somewhere check pipes to and from boost control solenoid and also manifold boost pipes this symptom is normally a split pipe or pipe has popped off

 

As above.

A good way to cheack for this is with a smoke tester...they are pretty pricey, but they are superb for this kind of job, so if you know somebody who has access to one its worth trying, as it makes finding leaks very easy to spot.

A quick acutator test can be done by taking the vacuum hose direct from the actuator to the turbo outlet (no T pieces, restrictors, solonoid etc) This eliminates the rest of the boost control system and the car should run at around 0.5 bar max (the purge solonoid and other pipework etc is what makes it run at higher boost).

Avoid driving the car hard and at high Rpms with it in its present condition until its sorted, as it will very quickly wreck the engine (if not already - from excessive bearing wear, due to them being overloaded).

 

thankyou guys for all your advice and help with crack on with this asap will let you no the outcome.

 

i cant see any pipes that have come off or look split and i dont no anyone with a smoke kit and other way i can check guys...?

 

?????

 

https://www.scoobynet.com/general-te...wrx-wagon.html

Look at the first page in this link. There is a picture of the hose connections. Check all of these, trace them back to check both ends of every hose.

I'd be surprised if it was anything else.

 

they all look ok tho im sure if there was a split or something i would be hard to pin point anyway is there an easy soloution maybe spraying some leak detector on the pipes seeing if any bubbles appear....????

 

ive found a place local that sell all sizes of silicone hose pipe so im just going to change all 3 hoses then hopefully should be fine

 

Don't forget to replace the restrictor pill.

 

you could try fitting a manual boost controler if it holds boost could be your boost control solunoide

 

where can i get that from buddy? will subaru stock that even tho mine being a wrx import..? also do i need to change intercooler hose and dump valve hoses do you think guys...?

thanks

 

Changing your boost pipes to silicone is a worthwhile upgrade but not essential, if the were faulty it would not give the sympoms you have. As we have already said it sounds like your actuator isnt doing its job properly which would be caused by a fault on one the pipes you have been checking. Where you based by the way?

 

He is talking about the small hoses from the BCS (boost control solonoid) and MAP (Manifold absolute pressure) sensors. There is no advantage in changing these to silicone apart from figuring out if these hoses are at fault. The OE items are perfectly suited to the job they need to do.

Personally I don't think you need to go to trouble of changing them. Just check them over and make sure they are all connected as they should be (as in the picture I linked to) and move on to the next thing.

You could try a dawes valve or similar to rule out the BCS though, but you will also need a boost gauge so you can see what you are doing. If the Dawes does solve the problem it is only masking the problem and you should still find the fault.

More importantly DO NOT drive the car whilst it is overboosting or you could do some serious damage. If you are not confident take it to a Subaru specialist, it may not cost a lot at all to fix.

 

thanks dan for all that, im only driving in low revs and i have a boost gauge so im makeing sure i dont boost over .7 bar , ive found someone else now who lives by me who is breaking a L REG wrx so im going to have his pipes off of there and maybe take the solonoid aswell, if this doesnt cure tho what else could it be i thought this is all it could be matey....?

im in essex clacton on sea guys.

 

If those second hand parts are in good working order and they do not fix the fault borrow the ECU as well whilst it is easy to get at one for a loan and try that to just to rule out something else. A bit of a shot in the dark but you never know!!

I forgot to ask before. Have you checked for error codes?

Defo have the whole lot from him. There should be a bracket that holds all of the sensors together, take all of it.

 

yea will do then matey! ive not had any engine lights come on and no error codes stored is it worth me changing the dump valve hoses as well as i have a bailey dump valve what do you think dan..?

thanks mate

 

Stick with the above for now. No harm in collecting a few spares though..

 

brill thanks matey ill let you no how it go's!

 

if its a split hose wouldnt it not boost right up instead of over boosting lads...?

 

If it were a leak after the turbo, ie through the intercooler or any of the hoses off the manifold then yes.

If the leak was around the BCS small bore hoses then it will overboost.