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-----Question-----
Hello Roland,
I am Guyana South america. i own a isuzu trooper 4ZE1 1988 I recently change my head gasket and seat the valves set timing I cannot get the engine to start, what I find is that the spark comming from the coil is low a tiny orange spark, can u help me with this problem.
Thank You
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Hi Roy,
I will assume that you have an electronic ignition system rather than a distributor with contact points. I would first measure the voltage to the (-) post of the spark coil when you are cranking the engine to verify that you are getting 12V to the coil. Then I would check the inside of the distributor cap for signs of cracks or arcing. And I would check the resistance of the rotor between the center button and the rotating tip. Finally, disconnect the center wire from the distributor cap and hold it 6 mm away from the cylinder head. Then while a helper cranks the engine observe the spark and then gradually increase the distance between the tip of the wire and the cylinder head while continuint to crank but look for any signs of arcing to occur at the other end of the wire where it enter the tower of the coil. If you get arcing at the tower it means that the coil high tension tower is leaking voltage to ground. Those are the standard tests and approaches to a weak spark.
Roland
P.S. It was recently the anniversary of the Jonestown mass suicide, a truly sad story. Is that very much of a memory for you in Guyana?
We here remember that we show a doc. every anniversary, that was a sad day here.
Any way the voltage to the coip when i switch on the is ignition coil is 12 volts the spark from the coil when i test it is low do u think that the crank angle senser is bad the distributor is the optical sense 1
AnswerHi Roy,
I doubt it is the sensor if you are getting spark to all the cylinders. It is more likely the part of the system that generates the spark. You could check whether the + wire at the coil is being grounded solidly by the engine control computer. Just put the ignition to run, then crank the engine via the nut on the crankshaft pulley ane observe for the oscillation of the voltage pulse as you crank the engine. I don't know which engine you are working with so I can't know how the crank (and cam?) sensors are set up on your engine. But if you can probe the wires of the sensors there should be 3 of them. One with 5V on it, one that is grounded, and one that is the signal wire. On the chrysler corp engines if you measure between the signal and the ground wires the voltage should be pulsing between 5V and 0.3 three times per revolution (if it is a 6 cyl engine). If you have the Mitsubishi 3.0L V-6 then you have to be careful that the spark wires are properly assigned to theit positions on the cap because they don't follow the firing order due to internal rearrangement in the cap. So if you put them on 1-2-3-4-5-6 arround the cap they don't actually fire in that order.
Roland
