There are several parts as identified in the diagram below:
#2. is a vacuum reservoir, it is a small vacuum tank to supply a backup or quick supply of vacuum to the modulator valve when called for.
#7. is a modulator valve, it modulates vacuum to the turbo depending on input from the ECM (engine conditions)
#8. is a solenoid, it simply is either open or closed depending on engine running or not. It tries to hold vacuum on the vacuum reservoir when the engine is shut off.
The vacuum solenoid #8 can be bypassed as well as the vacuum tank #2 for test purposes.
The modulator valve #7 should never be bypassed; if you do the turbo vanes would go to 100% all the time!
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Supporting Vendor and Moderator of LOST05 Jeep Liberty CRD Limited
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