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What 'controls' the Heater Control Valve vacuum ? (MCC) 940 NA 900 1993

uid 18083's pic
posted by  lucid on  Thu Jul 10 02:36 CST 2003
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last visit: Fri Oct 24 12:31 CST 2014
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I see the HC valve is vacuum-controlled, and am wondering how the MCC system influences this vacuum. (am replacing valve, hoses, and radiator today per FAQ advice).

I have diagrams for '93 940, but don't see anything obvious on page 156. My best guess is item 6/27, which is identified as "Servo Motor, throttle control", with inputs from 4/40 the MCC/CU. Could this be something like the IAC, but controlling the HC Valve vacuum?


--
Bruce Young, 940-NA, many 240s (one V8), '73 142, '71 144 (ex circle track car in CT), '67 144 (new), used 122 from '63 to '67






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New What 'controls' the Heater Control Valve vacuum ? (MCC) 940 NA [900][1993]
posted by  lucid subscriber  on Thu Jul 10 02:36 CST 2003 >


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