FD3s: Second Turbo kicking in very late

[DRFTR]

Hi

got a big problem on my FD3s:

the second Turbo is coming very late,
it varies from 4500 to 7500rpm.

only know it\'s not the ECU,
i tried both the original and the apexi power FC

hope anyone can help me

greetings Michael

[Grizzly]

I would suggest looking at the Charge control valve/Piping for it, i know some one that had a similar problem. Its also quite easy to test, Let the car idle for a few minutes then knock it off, if you now pull the vac pipe off the Valve there should still be a vacuum if its good.

If that doesn\'t help read the link below.
http://www.autosportracetech.com/RX-7/TurboTroubleshooting.htm

[Ricco_04]

I had similar problem on mine.  Turned out that when Mazda put the crate engine in they crossed 2 vac hoses around (like what Grizzly says)  My boost would come in at around 6krpm! :eek