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HVAC 700

posted by  someone claiming to be Don on  Thu Jun 19 02:42 CST 2003 [RELATED]

The ventilation system on my '90 745 Turbo is being interrupted by the swings in manifold pressure between vacuum and boost. When the engine goes into boost, the ventilation or air conditioning stops until the engine returns to vacuum. I have dismantled the passenger side of the dashboard and noticed what appears to be a number of small, coloured vacuum hoses. These hoses are similar in diameter to the electrical wires and are integrated into the wiring harnesses for the heater system. Does anyone know where the HVAC system receives vacuum from? I have poured over the engine compartment and can't seem to find any vacuum lines that might be feeding the HVAC system. Also, does anyone know if there is some sort of check valve that prevents boost from being sent into the HVAC vacuum control system? Thanks in advance for any comments.






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MESSAGES IN THIS THREAD

New HVAC [700]
posted by  someone claiming to be Don  on Thu Jun 19 02:42 CST 2003 >
  • New HVAC [700]
    posted by  Steve subscriber  on Thu Jun 19 03:25 CST 2003 >
    • New HVAC [700]
      posted by  someone claiming to be Vacuum  on Thu Jun 19 15:15 CST 2003 >
  • New HVAC [700]
    posted by  john sargent subscriber  on Thu Jun 19 03:29 CST 2003 >


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