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Thunderbolt iv ignition

redsnapper386

Regular Contributor
"guy's,i put in new wires,

"guy's,i put in new wires,plugs,rotor cap,dist cap.i have no fire on one plug.it is obvious to replace the ign.module,and ign.sensor.am i correct.also,would this cause rpm loss.thank's much.1986 350,260 hp,"
 
""i have no fire on one pl

""i have no fire on one plug"

I assume you are saying no spark to any plugs. Have you performed the ignition tests? The tests will tell you if the problem is the coil, optic sensor or ignition amplifier. If the optic sensor located under the rotor is covered in rust then it's a good chance it is part of the problem.

Tests for Thunderbolt Ignition:
W/ignition key on AND BILGE WELL VENTILATED OF GAS FUMES!!!

#1 - Connect your voltmeter neg. lead to the engine ground and pos. lead to the white/red wire terminal at the dist. It should read 12 volts.

#2 - If 12 volts is present, remove the coil spark wire from the distributor and connect it to a spark gap tester to ground. Remove the white/green lead from the dist. terminal. Turn the ign. key to on and strike the white/green lead to ground. If there is spark, replace the ignition sensor in the dist.

#3 - If there is no spark, substitute a new coil and repeat test #2. Now if you get spark, install a new coil. NO SPARK, replace ign. amp.

#4 - In #2, if there is No voltage present, disconnect the white/red wire and check it again for 12 volts. If 12 volts is present, replace the ignition sensor inside the dist. cap. If no 12 volts present w/it disconnected--ignition amplifier is shot and must be replaced."
 
guy's it is 1-plug that do

guy's it is 1-plug that does not fire at all.thank's for the instructions to do the test.i think i will replace all parts.thanks.
 
"Only 1 eliminates the ign sys

"Only 1 eliminates the ign system.Broken spark plug wire, switch it with another and see if the same one is dead or the new cylinder is dead.
Bad spark plug, replace with an old one and retest
Dead cylinder?"
 
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