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When I replaced the control Mod. in my distributor the instructions said to check the pickup coil for continuity if the car doesn't start.  I went ahead and checked it before I put it all back together.  there was not enough continuity to make the tester beep, but the ohm meter showed around 60000 ohms.  The car started, but I'm wondering what the listed resistance is suppose to be.  

gm ignition coils are usually around 980 OHMs..      i have a quick test to verify almost any pick up coil for function...


set OHM meter to 2K ohms..   2,000 ohms..    measure pick up coil...   500 to 1,500 ohms is expected....

change meter setting to 2 volts AC or 200 volt AC...   AC not  dc...  

spin distributer shaft...   you should see just over 1.0 volt AC ...  if you don't and the pick up coil has passed the resistance test...

replace the reluctor..  

now that you think i am totally crazy... perhaps i am..


but the magnet under the pick up coil or in the reluctor stack causes AC voltage to be generated as the shaft turns and the tips of the reluctor pass the tips of the pick up coil...

power transistors in the module look at this AC voltage...   they turn on when the ac voltage reaches 0.3 volts above actual 0.  this voltage rise is happening as the tips of the reluctor are approaching the tips of the pick up coil..    as the tips come together.. the voltage drops to 0 and then goes negative..   the power transistor opens the circuit as the voltage passes 0 this collapses the magnetic field built in the ignition coil primary...   the collapsing magnetic field in the primary passes through the secondary creating a high voltage pulse that eventually gets to the spark plugs...


reluctors fail in some designs...   the solid ones on some GM large cap HEI seem to last for ever.. but the small cap HEI designs have been known to have the magnet under the reluctor top plate crack.. this throws up what i describe as ghost signals causing the electronic timing control to go haywire..

when conventional reluctors fail.. they fail as in they don't retain enough magnetic field to create enough voltage to trigger the ignition module to turn the power transistor on..  then it can turn it off..

about the 0.3 volts above 0...    it will be doubled.. positive 0.3 volts and negative 0.3 volts..  this is 0.6 volts AC...  so you need to see almost 1.0 volts AC for the system to really work properly..




this is a reman distributer that replaces the reluctor design above.. it is far superior in creating seine wave output for the module and the computer to control.. this is a V6 version...

 

Wayne,  Your information is greatly appriciated and vert valuable.  I cannot thank you enough.