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Discussion Starter #1
I was coming home from a show and all of a sudden the entire car shut down. No dash lights, engine stopped running, nothing (I did not try and start it again, happen to fast)! As the car was just about to come to a stop, BAM, it powered back up again and the engine started running again (I did not shut the key off when it shut down)

I need to get the wiring diag out and take a look at it. What in the world would cause this to happen? Bad connection at the starter??
 

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I would be looking at any positve junction blocks or a ground to lose that much.
 

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Main power supply, connects at the starter.

I had this happen years ago and the main Positive cable shorted out on exh.

AL
 

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similar happened to me in my first gen, it was a bad connection at the fire wall where the front loom feeds to the fuse box....

bad connection at the horn relay? (junction point in the front end)

If your car died you prolly lost power the ignition, so follow your ignition feed (off the dist/coil) back to see where it's tied into 12v
 

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similar happened to me in my first gen, it was a bad connection at the fire wall where the front loom feeds to the fuse box....

bad connection at the horn relay? (junction point in the front end)

If your car died you prolly lost power the ignition, so follow your ignition feed (off the dist/coil) back to see where it's tied into 12v
X2 on the fuse block connection, had the exact same experience. Had the lighter wire go to ground months before and smoke the lighter wire all the way to the fuse panel. Months later the slightly melted main positive wire at the firewall plug finally lost contact.
 

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Discussion Starter #6
The main power connector at the fire wall, thats under the power booster correct? I'll also check the connections at the starter...

When this happen, I lost everything.. Tach went dead, engine, everything.. I have a electronic tach / shift light. When I turn on the ignition to start it the first time the shift light flashes.. That's what it did when everything came back on so, what ever this is, it cutting power totally.
 

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Discussion Starter #9
Also check the fuse link, and connection. It is inline from the positive battery terminal, right at the battery, at the core support. Had mine come loose/corrode, whole car died. It feeds everything......


T,
Okay, checked the connections at the starter and one was a little lose which is the one that controls the solenoid. I looked at the fusible link and both ends seem a little soft and you can see a little of the wire. So, I want to replace it.

Anyone know the rating of this fusible link?
 

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check battery

I've worked on a few older cars that did the same thing and have cured it by either tightening the battery cables or cleaning them. Even if they look clean give them a quick wire brushing, including the post. If you don't find any broken, burned, or corroded wires take a peak at your ignition switch, see if any of the terminals on the plug-in are burned. The battery could have a bad cell as well which in some few cases will short and cause the car to die and come back alive a few seconds later. Just start with the obvious things first and go from there.
 

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The main power connector at the fire wall, thats under the power booster correct? I'll also check the connections at the starter...

When this happen, I lost everything.. Tach went dead, engine, everything.. I have a electronic tach / shift light. When I turn on the ignition to start it the first time the shift light flashes.. That's what it did when everything came back on so, what ever this is, it cutting power totally.
I did have a tach wire ground and do the same thing you described
 

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Discussion Starter #12
Aside from not having two grounds and finding a fusible link that was questionable, I think I may have found the real cause. There was a yellow wire hanging out by the starter that was part of the same harness for the starter wires. The end was just stripped with no connector just hanging there which looked close to the bell housing. I think this wire goes back up to the main feed but I'm not sure.

I'm going to get under there to trace it out and see were it goes. The wiring hand book shows this being connected to coil. I can see this shutting down the engine but, the tach too? Remember I'm running an MSD system...
 

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Discussion Starter #13 (Edited)
I went and looked at the wiring diagram again and the yellow wire definitely comes from the coil (need to trace it on the car to verify). Also found out that this wire supplied a full 12 volts during startup only to the coil. This was because during startup the red wire from the bulk head that supplied voltage to the coil (which dropped the voltage down to 8 volts) would drop to about 5 or so volts during a cranking.
 

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I went and looked at the wiring diagram again and the yellow wire definitely comes from the coil (need to trace it on the car to verify). Why would the positive side of the coil need a connection to the starter? The coil has a wire connected to it that comes from the wire harness from the bulk head connector for 12 volts. So, why run a wire from that same point on the coil down to the starter??
There are 2 reasons! (1) is iffy!

(1) The original points system the power wire from the firewall is a resistor wire. Only suppling 9 volts to the ignition system. So they had a start Bypass, the yellow wire will supply 12 volts to the ignition while the engine is cranking.

(2 iffy) In some cars, the switch supply's no power to the ignition while "cranking", and the bypass does this. If your car has power to the ignition while cranking,(and your not running the factory points system) you do not need this wire. If your using the factory resistor wire for power to the HEI you need to change it. This makes a big difference on the ignition system. 95% of the time, not needed.

Al
 

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Discussion Starter #15
Thanks AL

I edited my post because I found out just what you are saying. That wire in my case is not needed at all... And I'm sure thats why my car died, it may have come in contact with the bell housing and shorted out the coil.

There are 2 reasons! (1) is iffy!

(1) The original points system the power wire from the firewall is a resistor wire. Only suppling 9 volts to the ignition system. So they had a start Bypass, the yellow wire will supply 12 volts to the ignition while the engine is cranking.

(2 iffy) In some cars, the switch supply's no power to the ignition while "cranking", and the bypass does this. If your car has power to the ignition while cranking,(and your not running the factory points system) you do not need this wire. If your using the factory resistor wire for power to the HEI you need to change it. This makes a big difference on the ignition system. 95% of the time, not needed.

Al
 

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Discussion Starter #17
Update

Well, after all this work I thought I had it fixed. Turned out it was still happening... I pulled the car out of the garage to start my epoxy floor project and it died... After taking another look at it i noticed I could get it to drop dead by playing with the key (not sure why I did not notice this in the past).. So, I installed a new switch and now it seems fine..:turn:
 

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my wagon is doing the same thing. i'll be driving down the road and all of the sudden everything shuts down, not cool at all. i have to pull over and re-seat the wiring harness on the firewall and it fires right back up.

i tried flexing out the connector pins on the wiring harness and the fuse block so they'll have a more solid connection but that hasn't helped, one of the wires must not have a sold crimp in the harness or something like that.
 

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Just went thru a similar problem on my 63. Looking at the engine harness connector on the firewall; There are 2 vertical rows of pins, the top pin on the left is the resistor wire to the positive side of the coil from the ignition switch, this is probably the one that's loose. The top pin is the solenoid wire to the starter from the ignition switch.
 

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Well....yesterday I drove my 65 wagon and all was great. Today I tried starting and it cranked over once (cold and it did not start on the first try). So I tried again and nothing. What do you guys recommend I start looking for? I am not a mechanic, but will try to fix things when I can to avoid the costly trip to the shop. All lights are on battery has charge, it just will not do anything at the key switch. :confused: Please get back to me guys, as this is my daily driver and I had to ride the bus (3 buses to get to work) today because of this.

Mando
 
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