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Home >> BMW >> 1987 >> 535is 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. Supply battery voltage to valve with jumper wire and ensure valve is properly grounded. Pull off relay No. 1. Apply battery voltage to connector No. 87 in relay plug and check that fuel pump runs. 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. Check Thermotimer as described in TEST 12  and replace if resistance values are not correct. See Figure . and Figure .
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