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Starting Problems - Battery Sparks, Car Starts By Itself

  • Thread starter Thread starter Ghost001
  • Start date Start date Jun 4, 2006
G

Ghost001

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#1
  • Jun 4, 2006
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Hello,

I did something I probably shouldn't have done (hindsight is 20/20, I guess).

I was having problems starting the car, and it seemed to have something to do with the positive battery cable. When I wiggled it, there was some power, but not enough to start.

So, what I did, which I probably shouldn't have done, was to connect the positive battery terminal to the place where the positive battery cable goes (starter relay), using a jumper cable.

Anyway, the car started, but I think the starter motor kept going and wouldn't stop. So, I turned off the car.

I walked to a Pep Boys and got a replacement battery cable (4 gauge), and replaced the positive battery cable.

Now, every time I connect the battery cables, first connecting the positive cable, there are huge sparks when I try to connect the negative cable.

The one time I actually had the courage to fully connect the negative cable, the car started turning over by itself, even though the ignition was off.

I'm guessing that there's a short circuit somewhere, or the ignition circuit or some starting-related circuit has gotten fused or stuck so that it's always on/connected.

Does anyone have any ideas?

I guess the lesson is, get the proper parts, rather than trying to use something for what it wasn't meant to do.
 

SVT32VDOHC

waiting for the next hack atta
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#2
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  • #2
I would check the starter selenoid, I just did a 2.3L to 5.0L swap, and that selenoid has to be right. The only wire that goes to the one side of it, is one negative cable. All of the rest of them go to the other side of the selenoid. Also, check you grounds. There is one on each side of the top of the core support. There are two on the driver side fender apron, (next to the battery), and there is one in back of the intake to the fire wall.
 
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Ghost001

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Thanks, SVT32VDOHC. I'll check all of that stuff out.

Is the "starter solenoid" the same thing as the starter relay? Is it that thing near the battery, to which the positive battery cable is connected?
 

jrichker

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Take SVT32VDOHC's advice & go with it.

If that doesn't work, the solenoid contacts will sometimes weld themselves together. Leave the postiive battery cable disconnected and use an ohmmeter and measure the resistance across the two big posts. You should see 1 megohm or more: If you see less than 1 .5 ohms, the contacts are stuck together. Sometimes you can unstick them by giving the back side of the solenoid a sharp smack with a hammer.
 
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Ghost001

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Also, what is the "core support"? Is it the battery tray?
 
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Ghost001

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jrichker said:
Take SVT32VDOHC's advice & go with it.

If that doesn't work, the solenoid contacts will sometimes weld themselves together. Leave the postiive battery cable disconnected and use an ohmmeter and measure the resistance across the two big posts. You should see 1 megohm or more: If you see less than 1 .5 ohms, the contacts are stuck together. Sometimes you can unstick them by giving the back side of the solenoid a sharp smack with a hammer.
Click to expand...

Cool, thanks jrichker! That sounds highly possible. I'll check it out.
 
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Ghost001

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I disconnected both battery cables, and measured the resistance across the 2 posts on the starter relay (is that the starter solenoid?).

I measured a resistance of 0.1 ohms.

So I guess I have indeed welded the solenoid contacts together. Or, maybe I've welded something else together.

I'll try the hammer trick, and then maybe get a new solenoid.
 

Fett

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  • Jun 4, 2006
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Yea, your starter solenoid took a dump. Replace it, and I would look into getting a 95 starter. You will need to run a trigger wire to the starter and move the cable from the solenoid to the battery, but you will avoid this problem in the future.
 

SVT32VDOHC

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#9
  • Jun 4, 2006
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Ghost001 said:
Also, what is the "core support"? Is it the battery tray?
Click to expand...

The core support is also caleld the radiator support. It is the top metal bar that your hood latch and cable is bolted to.

The starter selenoid is located above the battery. I bolts to the left fender apron, just infront of the left strut tower. IF you have a 5.0L, it is right next to the coil.
 
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Ghost001

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Is the "starter solenoid" the thing on the fender, near the battery? The positive battery cable, and a bunch of other wires, are connected to the rear post, and a single cable (negative battery cable?) are connected to the forward post.

I just want to make sure I was checking the right thing.
 
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Ghost001

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SVT32VDOHC said:
The core support is also caleld the radiator support. It is the top metal bar that your hood latch and cable is bolted to.

The starter selenoid is located above the battery. I bolts to the left fender apron, just infront of the left strut tower. IF you have a 5.0L, it is right next to the coil.
Click to expand...

Yes, I have a 5.0. By "left", do you mean driver side?

What is a "coil"?

Thanks for all of the info. I'm new to the Fox Body game, obviously.
 
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Ghost001

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In other words, is this the starter solenoid?

http://www.mustangmods.com/ims/u/2198/3911/62664.jpg
 
G

Ghost001

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#13
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Here are a couple more photos. This is the starter solenoid, right?

http://www.mustangmods.com/ims/u/2198/3911/62669.jpg

http://www.mustangmods.com/ims/u/2198/3911/62671.jpg
 
G

Ghost001

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#14
  • Jun 4, 2006
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Yep, you guys are right, it's the starter relay/solenoid.

I completely removed the starter relay/solenoid, and disconnected all of the cables from it, and measured a resistance of 0.1 ohms across the 2 big copper bolts/posts.

I'll try the hammer trick, as a temporary measure, and then get a new solenoid from a Ford dealer.

I may think about going to the 95 unit, as Fett suggested, if this is a common problem with these solenoids.

Thankyou for all of your help!
 
G

Ghost001

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Woohoo! The hammer trick seems to have worked.

The resistance went up to essentially infinity, after whacking it with a hammer.

And now, no more sparks when I connect the negative cable, no self-starting motor, and when I turn the ignition, the power doesn't just die, it actually stays on, although it's too low to start the car, probably because the battery is dead.

I'm going to recharge the battery, and try it again later.
 

jrichker

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BFH does the trick again
 

302RollinHard

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#17
  • Jun 4, 2006
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yes the BFH is one of the most under rated tools in the tool box, I have to agree with you. fixes starters, starter solenoids, stubborn header flanges, all kinds of stuff. Even fixes pesky women.
 
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