Hi all. I replaced the dreaded vacuum hoses with a nice racing yellow to match my black FD3S. Looks great. I initially changed them because I was getting boost spikes at high rpms. Now my primary turbo spools up great, and the car is more responsive. Only catch is that now my secondary turbo when it comes on, I get no boost at all. My boost is 8-10-0. (using an autometer boost guage | stock ecu).At around 5k - 5.5k and upwards, i get a sound like there is air being stuck in a vacuum. Only mods on the car are 2 k&n filter chargers (removed oem air box). I'm assuming that a hose may be crossed or maybe one of the solenoids is not opening. Once again, the primary turbo spools up, runs great, but the secondary is almost dead, and a terrible sound is heard after 5k. I'm assuming maybe the charge relief valve is stuck or the hose is incorrectly hooked up. Any help on diagnosing this problem would be great.
Thanks in advance.

 

Pull off the intake manifold and look for "kinked" hoses..

 

Your secodary turbo is working, thats how you are seeing 10 psi, if it wasnt working you'd only be seeing 5-6 psi max. Its most likely a hosed placed wrong, "kinked", or a soleniod but I doubt that. Just recheck everything.

 

If the car worked fine before it has to be a hose popped off, kinked, or in the wrong place.

 

i forgot how the boost pill works, but did you remember to pull it out of the old hose and put it in your new one? i'm not sure if this would cause your problem...just a thought. good luck!

mikey

 

Thanks all, for your help. It turns out that in the hose diagram, there are two hoses in front that show to be connected directly. Instead they had to be switched/crossed. Wished mazda would make a better diagram in the workshop manual. Once again thanks for your input. - The dreaded vacuum monster has been tamed (i hope).