Sequential Boost Leak
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Sequential Boost Leak
Ok I've tried my hardest with the search button keywords are just far to common and are in 8/10 threads.
I Have a 99 FD with BNR stage III sequential turbos fuel pump has been upgraded along with injectors, Ugraded radiator and a water to air intercooler all controlled by an Apexi Power FC. Exhaust is a 3" down pipe and 3" exhaust all the way through with a resonator in place of the the Cat.
She was tuned on a dyno to 14psi but would sometimes creep to 16psi. I was out on my Sunday drive when I noticed a drop in power upon inspection of my boost gauges I have discovered it will only build to between 11 and 12psi. It does hold boost and seems to run normal aside from drop in boost and a different induction sound at WOT.
I have checked every single inch of vacuum hose. I noticed oil seeping out where the Y-pipe joins on at the front I am unsure whether it could just be seeping through the gasket or if oil would not leak if it is sealed properly.
How would a boost leak test differ to a standard single turbo boost leak test? If required I can supply photo of y-pipe join that is seeping oil if need be.
I Have a 99 FD with BNR stage III sequential turbos fuel pump has been upgraded along with injectors, Ugraded radiator and a water to air intercooler all controlled by an Apexi Power FC. Exhaust is a 3" down pipe and 3" exhaust all the way through with a resonator in place of the the Cat.
She was tuned on a dyno to 14psi but would sometimes creep to 16psi. I was out on my Sunday drive when I noticed a drop in power upon inspection of my boost gauges I have discovered it will only build to between 11 and 12psi. It does hold boost and seems to run normal aside from drop in boost and a different induction sound at WOT.
I have checked every single inch of vacuum hose. I noticed oil seeping out where the Y-pipe joins on at the front I am unsure whether it could just be seeping through the gasket or if oil would not leak if it is sealed properly.
How would a boost leak test differ to a standard single turbo boost leak test? If required I can supply photo of y-pipe join that is seeping oil if need be.
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#8
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After chasing boost leaks all weekend and not finding anything except for one at the tee for boost gauge I've only managed to bring boost up .1 of a bar. I believe I have properly tested now due to all the reading and research I have done this weekend my symptoms are now as follows;
Low boost
Boost is roughly .2 of a bar low across entire rev range.
Strange secondary induction noise
After the transition 4500rpm when the secondary begins to boost the intake noise becomes a sort of squealing noise.
I'm properly stumped as I'm not the most mechanically minded person. Anyone have some ideas?
Low boost
Boost is roughly .2 of a bar low across entire rev range.
Strange secondary induction noise
After the transition 4500rpm when the secondary begins to boost the intake noise becomes a sort of squealing noise.
I'm properly stumped as I'm not the most mechanically minded person. Anyone have some ideas?
#10
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try and see if you can find a vacume hose diagram .. I know you have the upgraded ratsnest . and just study it . ALSO try your wastegate / precontrol solenoids ..
If those solenoids are passing tomuch boost its opening up the waste gate / pre turbo sooner .
but its rare for BOTH of them to go bad at the same time .
are you getting 14 psi from the primary ? then 12 from the secondary ? ? or 12 across the board?
ARE YOU getting the same results on your PFC . does the PFC say you are only getting 12 psi ?
If those solenoids are passing tomuch boost its opening up the waste gate / pre turbo sooner .
but its rare for BOTH of them to go bad at the same time .
are you getting 14 psi from the primary ? then 12 from the secondary ? ? or 12 across the board?
ARE YOU getting the same results on your PFC . does the PFC say you are only getting 12 psi ?
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