Turbosmart BLOW OFF & BYPASS VALVE KITS - Dual Port for: Subaru WRX (08+), Liberty_Legacy, Mazdaspeed_MPS 3, 6, CX7 - Manual (Page 5)

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5. Use the factory bolts to fit the new BOV onto the intercooler pipe. Remember to install the supplied gasket in between the
BOV flange and the intercooler flange. Reinstall the vacuum/pressure source to the nipple and the plumb back hose. Re-
install the engine cover. Start the engine and check for leaks.
IMPORTANT NOTES ON SETTING THE SPRING TENSION
- Adjustment to the BOV is made by rotating the cap. To increase spring tension rotate in the direction of hard, marked on the top of
the cap
- Rotate the cap in the direction of soft to decrease the spring tension – CAUTION Do not rotate the cap beyond the red indicator
groove
- With the engine at idle the exhaust ports should be closed off by the piston – the piston should be hard against the seat and not
floating or moving
- Free rev the engine and back off quickly, the engine should return to normal idle speed – if the engine drops below idle or stalls
increase the spring tension by half a turn
- Repeat this process until the engine free revs and returns to normal idle speed
- Test drive the car and ensure that when decelerating or changing gears that the engine does not backfire or stall. If backfiring or
stalling is noticed then check all connections made during the installation, otherwise increase the spring tension
TROUBLE SHOOTING
The following points should be checked if you find that your engine is dipping below normal idle, stalling or if the BOV is functioning
poorly. Please note, the following checks will cure 99% of problems experienced with a BOV.
-
Check the vacuum hose for splits, cracks, loose connection, kinking or any obstruction – old or fatigued hose may collapse
under vacuum causing an obstruction.
- With the engine running remove the vacuum / boost hose from the nipple in the cap of the BOV, there should a loud hissing
sound. The engine should idle poorly, double check by covering the end of the hose with your finger – otherwise the hose is
blocked.
- Check to see if the BOV is blocked or contaminated with dirt or debris.
- Ensure that the vacuum / boost source is not shared and that the vacuum source is directly from the inlet manifold.
- Check the seal between the intercooler flange and the BOV. Make sure the supplied gasket is installed and the BOV Flange
is secured on the intercooler flange with the two factory bolts.
- Ensure the spring clamps are secured on silicon hoses and fittings.