volvo 740 turbo staring ISSUE!!!

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Old 09-01-2018, 10:53 PM
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Exclamation volvo 740 turbo staring ISSUE!!!


HEY TEAM, IM CURRENTLY HAVING PROBLEMS WITH SPARK .
BACKGROUND: I BROUGHT THE CAR NOT RUNNING THAT WAS ALL OKAY THE ISSUE WAS THE RADIO SUPPRESSION RELAY THE RELAY ITSELF AND THE WIRING WAS ALL UGLY ETC SO I DECIDED TO BYPASS IT ( YES,BYPASSED) AND IT RAN NICELY FOR AROUND 2 WEEKS . I PULL UP TO THE GAS STATION AND IT STOPPED AND WONT START . ITS NOW BEEN 6 MONTHS SINCE OFF THE ROAD , SHES CRANKING OVER BUT HAS 100% NO SPARK , THE DISTRIBUTOR HAS BEEN NEWLY REPLACED AND UNDER 1 YEAR OLD , BUT I HAVE NOTICED THE HALL SENSOR PLUG IS QUITE LOOSE??. AND BEFORE YOU ASK IF I WAS RUNNING THE BLOW OF VALVE WHILE CAR WAS RUNNING THE ANSWER IS NO IVE ONLY JUST PUT IT ON THERE . ALSO I HAVE TESTED THE COIL AND ITS GIVING SPARK . PLEASE ANY INFORMATION WOULD BE APPRECIATED LET ME KNOW IF IVE MISSED ANY SORT OF INFO OUT THANKS
 
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Old 09-02-2018, 07:53 PM
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The Hall sensor may likely be the issue, look into that.
 
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Old 09-02-2018, 09:48 PM
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thanks for the reply lev , how do i check the hall sensor, also the plug has alot of play is what i was meant to say lol
 
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Old 09-03-2018, 09:38 AM
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Quick Hall sensor test: the tachometer needle does jump slighty as you crank engine over if the Hall sensor is working, but the needle lays dead if the sensor is not working.Full Hall Sensor Test: Undo the distributor connector. When the ignition is ON the Voltage between positive terminal (red lead -Nr. 3) and ground should be approx. 11V. Voltage between (blue lead - Nr.2; middle one) and ground should be 5V although if you put it on a scope you would see the sharp rise and fall from 12v to ground as the distributor rotates. Pulse frequency varies as rpm is increased. . Resistance between (black lead - Nr. 1) and ground should be close to zero Ohms. Undo connector from the control unit (above the brake pedal) and remove the sealing washers (plastic inserts on the side of the connector). Replace connector without cover or sealing washers.- Disconnect the/red and blue leads from ignition coil. - Measure voltage between terminal 24 at rear of control unit connector (blue lead) and ground. NOTE: Connector must be attached to control unit. Switch on ignition. Turn crankshaft by hand. Voltage should indicate OVER 1.8V each time a vane passes Hall generator. Instrument should read approx."0" (0 - 0.7V) each time an opening passes Hall generator. The correct voltage is less than 0.7V or more than 1.8V.
 
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Old 09-04-2018, 07:14 AM
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okay i've done that. the rpm needle is jumping fine, checked my coil today it had really good spark so thats okay , spark plugs have really weak spark so i called into a local auto sparky and asked him , he said its the rotor from dizzy causing the weak spark so ive ordered a new one and pick it up tomorrow . he was saying if the coil is good then its sending good spark to distributor but the rotor isnt sending out the correct spark across the spark plugs ??hope this sounds right we will soon find out...
 
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Old 09-05-2018, 02:52 AM
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that bright blue stuff ain't stock, someone has been tampering with this thing.
 
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Old 09-05-2018, 02:53 AM
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you said you replaced the distributor, so presumably it already has a new cap, rotor, and insulator disk in it, and a new hall sensor ??
 
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