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Won't start

70 StangMan

70 StangMan

Well-Known Member
Donator
Well it is a beautiful day down South so decided to go for a ride out in the country. Last week she fired right up, now it just goes driiiiiiiiii when key is turned. Battery is fully charged. Bad Solenoid ?? Bad voltage reg. ? Where should I start ?
 
Easy to test the solenoid by jumping between the two large posts and see if the engine cranks. Make sure it is out of gear if it's a manual.
 
First thing I would is check all the connections. Something might have came loose.

Did it make any noise when you tried to start the car? If not check the solenoid.
 
  • Think it might be the key switch. Got it running and couldn't get it to turn off. Removed the pos and neg cables from the battery and removed the key and it still ran until I popped the coil wire
 
Well after a new solenoid and a new battery to replace the one with a dead cell and she's firing on all eight again. And shuts off when key turned like it's supposed to. Yee Haa !!
 
70 StangMan said:
Well after a new solenoid and a new battery to replace the one with a dead cell and she's firing on all eight again. And shuts off when key turned like it's supposed to. Yee Haa !!
Click to expand...
Well Hell !! With the new solenoid installed I went out today and when I returned I could not turn the car off again. I checked the solenoid with the test light and getting power to the battery side post but as well getting power to the I post. Why is this happening ?
 
When you tested for the I post, was the wire on or off? You'll always have at least 9V to that post when the car is running. When you tested it, was the key in the OFF position? In this case, your test light cannot distinguish between 9V coming from the ignition switch and 12V coming from the starter solenoid. This is the reason why I never recommend a test light; instead, a digitial VOM is a much more useful tool.

Right now, no one will be able to tell you whether your problem is in the starter solenoid or the ignition switch. Meanwhile, disconnect the negative battery post so you don't run down the battery.
 
Midlife said:
When you tested for the I post, was the wire on or off? You'll always have at least 9V to that post when the car is running. When you tested it, was the key in the OFF position? In this case, your test light cannot distinguish between 9V coming from the ignition switch and 12V coming from the starter solenoid. This is the reason why I never recommend a test light; instead, a digitial VOM is a much more useful tool.

Right now, no one will be able to tell you whether your problem is in the starter solenoid or the ignition switch. Meanwhile, disconnect the negative battery post so you don't run down the battery.
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Randy the wire was on when I tested it and the key was off and the engine not running. I did notice that the light was brighter on the pos post than the I post.
 
Repeat the test with the wire off of the I post and let me know what you see. I cannot rule out that you have a bad ignition switch just yet.
 
Midlife said:
Repeat the test with the wire off of the I post and let me know what you see. I cannot rule out that you have a bad ignition switch just yet.
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Randy.. took the wire off the I post and test light did not light when touched to the post. Put the the wire back on the post and re-tested and it lit up ( rather dimly )
 
OK. That tells me that your starter solenoid is good, but your primary ignition circuitry is faulty. Are you running an aftermarket system by any chance? If not, power is continuously being supplied to the coil through the pink resistor wire regardless of the position of the key. Power should only go through that circuit when the key is in the RUN position.

Right now, you have a current draw on your battery, which will drain it in quick order.
 
Randy,
I am running a stock, regular elec. system except I changed to the Pertronix a few years back and everything has been fine. Until now.
 
Same thing in my old truck. Turned it off the other day and was like WTF? Disconnected battery and was like WTFx2? I just reached in and bumped the key to throw some juice and it cut off. Gotta replace my switch also.
 
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