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TR6 71 TR6 Ignition/Starting Issue

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BJones

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Hey guys, maybe you all can point me in the right direction.

My TR6 will crank and fire but will not continue to stay running. As soon as I release the key it dies. If I keep the key in the start postition, it will run until I release the key. One time out of about 100 tries, it stayed running. I have a petronix ignition that came installed when I bought it. Any ideas of where to start troubleshooting would be appreciated.

Thanks for the assistance as always.

Brent
 
If it "runs" in the start position, then I would not suspect the pertronix. I would suspect the ignition switch first.
Others will be here shortly and may have other ideas.

Have you checked for power to the coil when the key is in the run position?
 
Has your ignition switch been worked on or been taken out recently? If so, it could be wired wrong.
 
Some TR6's have a 'resister' wire that powers the coil at a lower voltage while the ignition is in the RUN position. The START position bypasses the resister, so full power goes to the coil. The 'resister' is built into the wiring harness and is one of the most fragile wires in the system, and easily broken. Just because your car originally had or didn't have this wire is no reason to not check it out closely, since many have been altered. Don't hot wire the coil until you're sure the coil will handle the lack of a resister.

If you look hard enough, you'll find the problem.
 
The ignition switch has not been out since I have had the car. I thought maybe the switch could be the issue, however the radio will work when in the "on" position. So I figured the switch was working correctly. Is there a way for power to go to the radio but not the rest of the car in the on position?

Thanks!

Brent
 
My coil has 3 wires that come off of it in addition to the coil wire. 2 go to the distributor/petronix, red and black and one that also attaches to the red side goes back to my fuse panel. I was able to take a multimeter and successfully run a continuity test from the coil all the way through the wire and fuse. I am not sure if it is a resister wire or not.

Thanks,

Brent
 
Sounds like you do not have the resistor wire... if you did, you would have two wires going to the pos side of the coil--
A white/yellow stripe going to the starter relay, and a pink/white stripe going back to the ignition switch.
Also, I don't believe that the '71 had the resistor wire to begin with; although it could have been changed over the years by a previous owner.
 
I agree. Check out the wiring diagrams here: https://www.advanceautowire.com/tr2506.pdf

It sounds like it's wired correctly. Use your multimeter and with the key turned to RUN and you should measure +12v at the coil + side (where the red and white wires are connected) to GND. I'm guessing you have a defective ignition switch, but I'd also expect the radio to not work. I don't see the radio on the wiring diagram. Does the wipers and heater fan work only with the key in the RUN position?
 
You may want to disconnect the pertronix wire... they don't like to be powered up for some time without running or you run the risk of burn-out of the unit.
 
Clip a voltmeter on the power side of the coil, other lead to ground. Watch the meter, start it, if the voltage goes away, wire, connector or ignition switch is bad. It's just logical troubleshooting after that.
 
Ok, some quick testing and this is what I have to report. I turned the switch to the run/on position and I did not have wipers, heater fan or turn signals. I quickly hooked up the multimeter to the positive side of the coil and it read zero. I had my father bump the starter while I had the multimeter in place and I was able to get 8.5 volts. Looks like it is the switch. Is there anything that can be done to by pass the switch and make 100% sure it is the switch? Maybe directly wire something and see if the wipers or heater fan work?

Thanks,

Brent
 
When you turn the ignition key to "ON", a white wire from the switch should deliver 12 volts to the fuse that protects the Green wires AND feed 12 volts to another white wire on that same fuse box terminal. It's that wire that goes to the + terminal of the coil.
All the things that you said were not working are fed by the fused Green wires.
The white wire to the coil is not fused it is fed directly by the white wire from the switch and is "upstream" of the fuse, or at least it is supposed to be.

So you need to see what the White wire from you switch is doing..Maybe the switch is bad, not transfering power from one terminal to the White. Maybe the Whte wire is disconneced or broken.
 
I checked the back of the ignition switch and the spade terminal for the white wire was loose. I applied pressure to the back of the switch while the key was in the "ON" position and my heater, wipers and turn signals all began working. I then started the car while holding the back of the switch and the car fired and stayed running!!! I released the back of the switch and the car died. Problem found. I have 7 spade switch and found one in the UK to replace it.

I couldn't have figured this out without you guys!!!

Thanks sooo much.

Brent
 
We are all here to help each other... glad you got it solved!
 
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