faulty bov?
07 August 2010, 04:38 PM
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faulty bov?
What are the symptoms of a faulty dump valve?
My 97 wrx has a forge bov fitted (the one in the link below)
http://www.forgemotorsport.co.uk/con...duct=FMDVGTO14
I have my doubts its working as it should so opened it up to see if a spring was broken but there fine so just re-greased and re assembled it .
tia
My 97 wrx has a forge bov fitted (the one in the link below)
http://www.forgemotorsport.co.uk/con...duct=FMDVGTO14
I have my doubts its working as it should so opened it up to see if a spring was broken but there fine so just re-greased and re assembled it .
tia
07 August 2010, 04:51 PM
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Depends how it is faulty. With an aftermarket DV there's also a delineation between a faulty unit and one that is working nominally, but is incorrectly adjusted for the engine.
To answer your question, mainly poor throttle response, inconsistent or disappearing boost, poor idle consistency, engine cutting out when you roll up to a standstill, hearing compressor stall when you lift off under boost, jerking/cutting out during gearchanges, that sort of thing. There are clearly other potential causes for all of the above symptoms though.
To answer your question, mainly poor throttle response, inconsistent or disappearing boost, poor idle consistency, engine cutting out when you roll up to a standstill, hearing compressor stall when you lift off under boost, jerking/cutting out during gearchanges, that sort of thing. There are clearly other potential causes for all of the above symptoms though.
07 August 2010, 07:46 PM
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Depends how it is faulty. With an aftermarket DV there's also a delineation between a faulty unit and one that is working nominally, but is incorrectly adjusted for the engine.
To answer your question, mainly poor throttle response, inconsistent or disappearing boost, poor idle consistency, engine cutting out when you roll up to a standstill, hearing compressor stall when you lift off under boost, jerking/cutting out during gearchanges, that sort of thing. There are clearly other potential causes for all of the above symptoms though.
To answer your question, mainly poor throttle response, inconsistent or disappearing boost, poor idle consistency, engine cutting out when you roll up to a standstill, hearing compressor stall when you lift off under boost, jerking/cutting out during gearchanges, that sort of thing. There are clearly other potential causes for all of the above symptoms though.
Having problems with a slight judder when in boost .
Thanks for the reply .The search for the fault aint going to be easy
07 August 2010, 11:15 PM
#4
Opening up the dump valve on a forge and seeing if the spring is broken,is not going to tell you anything. Mainly because the springs rarely break,they just weaken,which allows the piston to stay open and you cant see this when you have it on the bench.
You could try : 1. ordering a brand new spring from forge(£8 - £9) and see how you get on . 2. If you still have your std recirc valve, try fitting that then go out for a drive and see if the problem still occurs - if it does then its possible it might be something else.
You could try : 1. ordering a brand new spring from forge(£8 - £9) and see how you get on . 2. If you still have your std recirc valve, try fitting that then go out for a drive and see if the problem still occurs - if it does then its possible it might be something else.
08 August 2010, 06:39 AM
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The tmic had been changed for an sti one by the previous owner and i dont have the original reciirc valve.
I'm also going to get rid of the cone filter and refit an airbox.
I'm also going to get rid of the cone filter and refit an airbox.
08 August 2010, 05:16 PM
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I'm also going to get rid of the cone filter and refit an airbox.
If the latter, sure, refit the standard induction tract in its entirety (making sure you use a quality filter). If, however, the car has been mapped properly for the cone, you will likely find it won't run properly/as intended.
08 August 2010, 06:59 PM
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Worth buying an OE one.
One note of clarification/caution before you do this, as your thread's a little lacking in context: Is the car mapped for whatever modifications it is running (including the induction kit), or has the cone simply been thrown on in the past without rescaling the airflow-voltage curve?
If the latter, sure, refit the standard induction tract in its entirety (making sure you use a quality filter). If, however, the car has been mapped properly for the cone, you will likely find it won't run properly/as intended.
One note of clarification/caution before you do this, as your thread's a little lacking in context: Is the car mapped for whatever modifications it is running (including the induction kit), or has the cone simply been thrown on in the past without rescaling the airflow-voltage curve?
If the latter, sure, refit the standard induction tract in its entirety (making sure you use a quality filter). If, however, the car has been mapped properly for the cone, you will likely find it won't run properly/as intended.
I have no record in the history of it being remapped and tbh i would think the pre owner has just stuck the induction kit on.
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