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Resolved New Solenoid went bad instantly

  • Thread starter Thread starter dbix11
  • Start date Start date Jun 19, 2023
D

dbix11

Member
Aug 17, 2021
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Western Mass
Jun 19, 2023
#1
  • Jun 19, 2023
  • #1
Ive been enjoying the Mustang this season, before winter i had the battery, starter, and distributor replaced. The car has been firing right up, until a few days ago. I went to start it and got that single click, and then power would be cut for a bit. As in'd turn the key and accessory power was GONE. Id come back and try again and ACC power would be back and id try to start the car and get the one click- power off again for a bit.

I did the trick of jumping the solenoid and would get the one click at the solenoid. I read some forums, watched some videos and figured the solenoid was the culprit. Went and got a Solenoid at advance auto parts (Car Quest I think. The one i took out was motocraft) Did the swap and got in the car, turned it on and VROOM started right up. I was incredibly relieved.

I turned the car off, and went to fire it up again and then *click.* The solenoid seems to have gone bad INSTANTLY. As i mentioned every time the car has started it fires right up, there's nothing wrong with that sequence

I'm not a mechanic nor would i really call myself an amateur and i dont know where all my grounds are located (would need pictures). The starter is a high-torque one from LMR (if that matters) The odds that two solenoids would be defectively bad in the same way seems very low. The solenoid isn't hot, no smoking or burning etc... I opened up the solenoid i took off and nothing seemed burnt or obviously messed up.

I could get another solenoid to repeat the issue for 20 bucks. Though if i have to ill replace the solenoid, start the car and proceed to drop it off at my mechanic if i can't get it figured out here. Idk if this solenoid is toast now or not. if it's bad after one good start then i have a big electrical problem.

Thanks everyone
 

AeroCoupe

lube between the nut and the face. I know my lubes
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#2
  • Jun 19, 2023
  • #2
So now when you turn the key do you have power or is it dead like before? If you do have power then the mini starter has a solenoid on it so that could be bad.

If you do not have power then you should start checking grounds. Battery will have one so check it first as well as ensuring the battery cable connections at the battery itself are good. If all this checks out then you need to do voltage drop tests on the battery cables.
 
D

dbix11

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Jun 19, 2023
#3
  • Jun 19, 2023
  • #3
Itll have power if I leave it alone for a bit. However, if i turn the ignition and get the click i lose all power. It has the feel of a thermal fuse, where you'd need to wait for it to cool down before the circuit re-closes. Obviously, it's not that.. but that's what it feels like.

I can go outside now and turn the key to acc and ill have power, but if i go to start, ill get the click and the power will be out for a bit.

It was doing this before i changed the solenoid, when i changed the solenoid out the car started up perfectly (the first and only time.) However, when i turned it off and tried to turn it on again it was the same issue as the previous solenoid.

Something is happening to the solenoid that damages it instantly it seems.
 

Mustang5L5

That is…until I whipped out my Bissell
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#4
  • Jun 19, 2023
  • #4
If it’s clicking, that suggests the internal contacts are shifting. Have you tested for continuity between the two main posts to see if there is a common path bridged between the two?

Usually “click and dead” type situations indicate a high resistance connection somewhere that it arcing out and losing connection. Usually a bad battery terminal or broken lead or a bad ground. They usually can be warm to the touch after doing it a few times.

Working when swapping the solenoid for a bit might suggest you remade the connections well enough to temporarily work but it eventually arced out.

I would spend the time going over everything and sanding all the connections to ensure good solid contact. Clean the battery terminals and all the grounds as well. Sand the terminals down to clean metal, reinstall tight and retest.

With solenoid in hand, you can test with a 9v battery with alligator clip leads. Black to the body ground and red to the small post. Solenoid should click and you should have continuity between the two main posts. The fact you are hearing this suggests this is happening and the issue is a bad/loose/dirty connection somewhere when load is placed on it.
 

General karthief

wonder how much it would cost to ship you a pair
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#5
  • Jun 19, 2023
  • #5
Bad connection at the battery.
 
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limp

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#6
  • Jun 20, 2023
  • #6
General karthief said:
Bad connection at the battery.
Click to expand...
Has the Battery been load tested?
How old are your battery cables? they can corrode from the inside....
Start at the EASY parts first.....

After I did a frame off resto on the Truck in the pic, I was having problem with lights, slow cranking etc...EVERTHING was new on it....
POS Exide battery had a bad cell in it.. BRAND NEW battery...
Found it when my parts store owner friend tested each battery cell with a device that sucked water out of each cell.....
 
Last edited: Jun 20, 2023
D

dbix11

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Aug 17, 2021
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Jun 20, 2023
#7
  • Jun 20, 2023
  • #7
Every ground i was able to find tested 12.6v. On the solenoid one was at the expected 12.6 , and the extremely populated one was at 8.8v, idk if thats normal or if its a clue. Also there is audible continuity between the 2.

What exactly is happening that causes my car to not have ACC power after it clicks, is that on some sort of timer, or is there a swelled contact that needs to cool down and revert to its normal size? that seems a bit confusing to me. I can make it click at will at the solenoid jump but i only get 1 chance at the ignition every half hour or so.

Ive taken the connections at the solenoid and battery and ensured its all flush and straight metal and tight
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,255
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Massachusetts
Jun 20, 2023
#8
  • Jun 20, 2023
  • #8
It's arcing. You have a bad connection somewhere.

The 8V is a clue. If battery voltage is 12V but you test that post and get 8V, i would take a good hard look at the POS battery cable. It's possible it's falling apart inside.
 
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Mustang5L5

That is…until I whipped out my Bissell
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#9
  • Jun 20, 2023
  • #9
dbix11 said:
the extremely populated one was at 8.8v, idk if thats normal or if its a clue.
Click to expand...

It is. It's possible you have a bad connection between battery and the solenoid. Perhaps a bad cable internally.

Is it always at 8.8V? What about after the car clicks and is dead? What's the voltage there.

This is a big clue. You should always have battery voltage on this post on the solenoid. The fact you are losing it still suggests a bad connection, or a high amperage draw somewhere. But in the case of the latter, someone would be getting pretty warm and your battery would be discharging

dbix11 said:
What exactly is happening that causes my car to not have ACC power after it clicks, is that on some sort of timer, or is there a swelled contact that needs to cool down and revert to its normal size? that seems a bit confusing to me. I can make it click at will at the solenoid jump but i only get 1 chance at the ignition every half hour or so.
Click to expand...

So can you clarify here.

Starting with the key gives you one ckick and then nothing? If oyu pull the small wire of the small post and test for 12V there when you turn the key, do you get it each time?
 

AeroCoupe

lube between the nut and the face. I know my lubes
Founding Member
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Jun 20, 2023
#10
  • Jun 20, 2023
  • #10
The “extremely” populated side of the solenoid is the same side the battery connects to, correct? You need to take all the wires off of it and just connect the battery wire up to it. Does is measure 12.6V+? If so you will need a test light to do the rest. Clip the test light to the same post the battery wire is connected to on the solenoid. Take the other end and touch it to each wire that was connected to the same side of the solenoid one at a time. If the test light comes on then you have a current draw on that wire. With the ignition off you should not have a draw.

Mike, check me on this.
 
D

dbix11

Member
Aug 17, 2021
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Western Mass
Jun 20, 2023
#11
  • Jun 20, 2023
  • #11
Humbly, I return to you fine folks which will give this problem a resolution. It would have been better if my car didn't start after replacing my solenoid, all it did was confuse me more than I needed.

Anyways, I left my keys in the acc position and decided to just start tapping random things and sure enough tapping on the positive terminal closed the circuit and returned power.

Switched it out and now it works of course.

Uploading a picture of the interior of the battery cable.

Thanks for everyone's interest, input, and patience. Great advice in these forums.
 

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Mustang5L5

That is…until I whipped out my Bissell
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Jun 20, 2023
#12
  • Jun 20, 2023
  • #12
Ford still makes a Motorcraft replacement cable.

WC-8751-A




 
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rednotch

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And its junk.... Hardware on mine rusted solid in less then a year lol
 

General karthief

wonder how much it would cost to ship you a pair
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#14
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The condition of that wire tells me there has been a connection problem for a while.
Also that type of battery connection needs periodic cleaning and tightening, better to have a cable, in a larger size, with a battery connection swedged (is that the correct word?) to the cable.
Just say'n
 
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85GTStangGuy

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#15
  • Jun 20, 2023
  • #15
rednotch said:
And its junk.... Hardware on mine rusted solid in less then a year lol
Click to expand...
Wow, that's disappointing. Would've hoped for better than that from a Ford part.

General karthief said:
The condition of that wire tells me there has been a connection problem for a while.
Also that type of battery connection needs periodic cleaning and tightening, better to have a cable, in a larger size, with a battery connection swedged (is that the correct word?) to the cable.
Just say'n
Click to expand...
Close.... I think the word you're looking for is swaged.
 
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limp

wrap a little cheese around it and its a done
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#16
  • Jun 21, 2023
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Mustang5L5 said:
Ford still makes a Motorcraft replacement cable.

WC-8751-A




Click to expand...
The cable I purchased from LMR looks very close....
 

limp

wrap a little cheese around it and its a done
5 Year Member
Oct 4, 2020
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Florida
Jun 21, 2023
#17
  • Jun 21, 2023
  • #17
General karthief said:
The condition of that wire tells me there has been a connection problem for a while.
Also that type of battery connection needs periodic cleaning and tightening, better to have a cable, in a larger size, with a battery connection swedged (is that the correct word?) to the cable.
Just say'n
Click to expand...
The worst battery connectors made......
 
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