dieing 79 cougar August 21, 2008, 09:09:54 AM I am having one of those cars I cant figure out. 79 cougar xr7 302. We put a new intake and Holley on it. Put gear drives on, and for maintenance a new dist., coil, and module. I put spacers under the module to give it air. My problem is when the car heats up it dies. put another new module and dist. in at different times and still dies. Went after the ignition switch, it was not burned. That is where I am stumped. I did notice the orange wire was HOT! I removed the pigtails that go to the dist. and wired them straight except the dist pigtail. that was 3 connections in 18 inches of wire. Now the orange wire does not get hot. I get 7 volts at the coil, but when I unplug the module it goes to battery voltage. Normal? What am I missing I know at this point it is something small. My specialty Is new cars the old ones, electrical like this one, somewhat baffles me. Quote Selected
dieing 79 cougar Reply #1 – August 23, 2008, 03:34:26 AM Which dura spark system is it? Quote Selected
dieing 79 cougar Reply #2 – August 23, 2008, 07:40:16 AM Quote from: rmestep;232981 I get 7 volts at the coil, but when I unplug the module it goes to battery voltage. Normal? What am I missing I know at this point it is something small. My specialty Is new cars the old ones, electrical like this one, somewhat baffles me.The module is suppling the coil ground, so there will be a voltage drop across the coil... This is why on this old stuff, it's not a good idea to use the "on" position to operate accessories... The current draw will soon run down the battery, also possible to damage the coil and or module... This is also true of a points system, unless they just happen to be at a open position...The newer systems will only supply coil ground while cranking/running, so there isn't any current drawn across the coil(thus you'll read battery voltage)...For your problem. Is there a resistor wire in the circuit to the module???? If not it's probably overheating and shutting down... Quote Selected
module Reply #3 – August 24, 2008, 10:51:06 AM The module is mounted on the fender I think it is a duraspark 2. The wiring is all original, We just got this car. I do not know where the resister is, The wiring diagram shows one in line somewhere. Was told it is shorted so I was just going to run 2 new wires and install a resister between the wires going to the coil and module as shown in the wiring diagram. Would this be a good Idea or not? I was wrong, After removing the pigtails and running the car the orange wire still gets hot, and dies. But the wiring harness looks better so I guess that is a plus at least Quote Selected
dieing 79 cougar Reply #4 – August 24, 2008, 11:33:08 AM here are a couple of things to work by............... Quote Selected
wiring diagram Reply #5 – August 24, 2008, 12:03:30 PM Thanks jcassity that is a similar diagram that I have. I have 3 that are showing different color wires, but all the same position of wires. I have one from Haynes, auto zone, and alldata. If I was going to replace the resister, What wattage one should I use? I know the ohms is 1.1. Or do you know where the original resister is? None of the books I have read shows where it is to check it. Quote Selected
dieing 79 cougar Reply #6 – August 24, 2008, 02:18:18 PM The resistor is built into the harness, it's a special piece of wire made of nichrome.. Usually has a pink rubber coating and is probably 2ft in length(they seldom fail, but my folks new '79 Cougar shorted a D/S module and burned up the harness)... If you were to use a external resistor, I'd guess it would need to be 20-25 watts... Any idea what the value of Chrysler's external resistor is??? Quote Selected
dieing 79 cougar Reply #7 – August 24, 2008, 05:17:46 PM The fact that you have 7 volts on the coil when the module is grounding the other side and 12 volts when the module is out means the resister is in there.You are dropping 7 volts across the coil and 5 volts across the resister. This is normal.I'm not sure having the module lifted off the metal of the car is better for conducting heat away. Quote Selected
dieing 79 cougar Reply #8 – August 24, 2008, 05:26:14 PM The orange wire goes to one side of the stator coil in the distributor. The purple wire goes to the other side if the stator coil.Does the purple wire also get hot?Did you have this problem with the original distributor? Quote Selected
dieing 79 cougar Reply #9 – August 24, 2008, 05:51:44 PM With the four wire connector to the module disconnected.The resistance between the harness terminals that mate with the orange and purple module wires should be 400 to 1300 ohms.This is the resistance of the stator coil.The resistance between these same terminals and distributor base (ground) must be greater than 70,000 ohms. Quote Selected
Topic: dieing 79 cougar (Read 934 times)
previous topic - next topic
