1969 Chrysler 300 Voltage drop at the coil

RDHOG

New Member
Joined
Feb 16, 2022
Messages
32
Reaction score
27
Location
New Hampshire
Long story shortened last year car ran great parked for the winter started out this spring and have a problem with voltage at the coil. I installed a pertonix pickup and a 12 volt coil jumped out the resistor. Now after about 20 miles the car won't say running t only has 7 volts at the coil if I run a hot jumper wire from the battery to the coil it runs fine. I have change alternator I have changed battery. Any ideas
 
Disconnect the wire to the coil, turn the key on and check the voltage again. If you get 12v using this method, most likely your coil is shorted and drawing excessive amperage and dropping the line voltage. Other possibility is that the line to the coil has a bad splice someplace that is corroded and dropping the voltage/

Dave
 
I was thinking that I needed to inspect the hot coil wire to see if I can fine where the voltage drops down line. because if I add a 12 line direct from the battery it starts and runs fine. I do have a second coil I could try. I was going to try and measure the resistance on the original hot
coil wire. I have cleaned the bulkhead connectors also.
 
LOAD test the voltage to the coil prob a bad connector.
 
By dumb luck I think I found the issue. I was out messing with the power probe this morning checking voltage and this was very loose .how it loosen up makes no sense I didn't touched it but I am sure this was my problem. Thanks for everyone's help as soon as I get a chance I will let everyone know

20240710_093225.jpg
 
By dumb luck I think I found the issue. I was out messing with the power probe this morning checking voltage and this was very loose .how it loosen up makes no sense I didn't touched it but I am sure this was my problem. Thanks for everyone's help as soon as I get a chance I will let everyone know

View attachment 670753
Those are called "temporary" terminals for a reason. They aren't made to be a permanent repair or replacement. That particular one has been over-tightened and will eventually crack and fail. .

I suggest changing the cable so you have a good terminal at both ends.
 
Back
Top