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Home >> BMW >> 1988 >> 528e Standard >> Repair and Diagnosis >> Engine Performance >> System >> MOTRONIC CEC System >> Testing >> Test 4: Cold Start Valve >> Valve Does Not Open
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Valve Does Not Open

  1. Remove valve, leaving fuel lines connected. Energize fuel pump. Supply battery voltage to cold start valve with jumper wire and ensure valve is properly grounded. Cold start valve should deliver fuel. If not, replace valve.
  2. If valve functions, check spray pattern and flow rate. Pull plug off valve and connect volt/ohmmeter between wires of plug. Start engine. Meter should read battery voltage while cranking engine. If not, trace circuit and repair wiring. See WIRING DIAGRAMS  at end of this article. Check thermotimer as described in TEST 12  and replace if necessary.
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