500 sec not starting

matt-tom

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Hello,

Myself and a friend are trying to save a 500 sec from the scrap heap and have managed to get the car from the owner but cannot get it to run.we have a strong smell of fuel but no spark, we have only tried a new coil so far with no joy we have also removed the alarm but that didn't help either, are there any obvious things that would stop it sparking ? (possibly the ignition control module ? )

thanks in advance

Matt
 

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Hello and welcome you need to check if you have 12 volt going to the plus side of the coil
 

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i'm sure that is one of the things that has been checked already :(

In that case try the minus side of the coil that should have 12volt on and off, as the engine is rotated, owing to the poor gate times of a digital meter, its earlier to see with a bulb. The engine needs to be turned over slowly to see it,
 
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matt-tom

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In that case try the minus side of the coil that should have 12volt on and off, as the engine is rotated, owing to the poor gate times of a digital meter, its earlier to see with a bulb. The engine needs to be turned over slowly to see it,


that did confuse us for a bit as we did have 12 volts at the minus side and i'm sure pulsed as well but realised that it's correct
 
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matt-tom

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Checking the minus on the coil would confirm the switching side was working[/QUOTE

ah ok there seems to be a sensor that comes from the dizzy to the ignition module do these pack up at all ?
 

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Checking the minus on the coil would confirm the switching side was working[/QUOTE

ah ok there seems to be a sensor that comes from the dizzy to the ignition module do these pack up at all ?

There are two types magnetic and optical. and yes they can pack up, if there is enough free play in the rotor arm, with the ign turned on this can sometimes be rocked to trigger the coil, and check the spark.

As long as there is 12 volt on the plus on the coil, when the sensor triggers, it purely grounds the minus side of the coil, as it opens again, the magnetic field in the primary of the coil collapses back into the coil and pushes the high voltage out of the secondary to fire the plugs, and at this point it is known as the firing stroke.
 

brandwooddixon

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From what you say the coil appears to work.
Have you checked that the spark plugs actually spark? Take out, plug into lead and leave resting on engine to ground it, turn engine over.
If they spark then check that the leads are connected in the correct order.
 
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matt-tom

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thankfully it was the ignition control module that was giving us no spark and it now runs, we even gave it a wash and a polish as the sun was out, it's going to need a fair bit more tlc to get us to our planned destination(Le Mans 24 hour race) but the project is still on going
 

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