Starter, Solenoid, Clutch Safety Switch, OR??

Hey guys, I need some help. I have a 92 Mustang 5.0 and just recently when I go to start it it would just click (like it had a bad starter solenoid), but after a couple times of trying to start it, it would fire up. Apparently the problem has got worse because now it won't start at all. All I get is 1 click. So I cleaned the battery cables and nothing. I tested the battery for voltage and it's got 12.19 volts, so the battery is good. So I bought a new starter solenoid and installed it and still just 1 click.

So before blindly throwing more money at this, I decided to do a search online for the problem and I ran across some videos where guys were having the same problem as I am and it turned out to be the clutch safety switch. So the guy in the video unplugged it and jumped the wiring by installing a fuse in the plug wire. I just got done trying that and still just 1 click and no start. The click sounds like it's coming from the area of the starter solenoid (which is on the drivers side inner fender by the battery).

So I have a couple questions....
1) If the starter was bad, would I hear just 1 click from the starter solenoid or should I hear multiple clicks like it would do if it had a dead battery?
2) Is there anything else that could be causing this problem, like a relay in the fuse box or something like that or is the starter the only other item that could be causing this?
3) there is a small metal square thing on the positive side of the starter solenoid post, but I don't know what it is or what it's for. Is this some sort of circuit breaker? Could this be the problem? As you can tell I'm just spit-balling for ideas.

We have 15" of snow on the ground right now and we're getting ready to move and I don't have much time to figure this out. Any idea or thoughts on where to look next? Is the starter the problem or something else. Thanks for any help and advice you guys can provide.
 

Rdub6

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Fully charged battery should be 12.6 or better. May want to start there before you get too deep. Plus you’ll want a good battery for any testing you’ll be doing anyway. There’s a couple good “no start” checklists around here that will be sure to find your issue.
 

Rdub6

So while I wait to figure out my rear end issues
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Is there a way to “bookmark” pages in my own settings? ....... like my own “favorites”
.... although I knew you’d come through with the link. ;)
 

Mustang5L5

Put lubricant all over the balls
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Test the solenoid directly.

Step 1, make sure car is in nuetral.

Step 2, make sure car is in nuetral

Step 3, turn the ignition to on, remove the small wire on the top post of the solenoid. Jump the small post terminal to the side of the solenoid with all the positive connections. Starter should crank and engine should turn on.

If you get the 1 click, you issue is likely a bad/loose connection. Start by removing the conditions and clean them up. Reattach and tighten up well.
 
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Test the solenoid directly.

Step 1, make sure car is in nuetral.

Step 2, make sure car is in nuetral

Step 3, turn the ignition to on, remove the small wire on the top post of the solenoid. Jump the small post terminal to the side of the solenoid with all the positive connections. Starter should crank and engine should turn on.

If you get the 1 click, you issue is likely a bad/loose connection. Start by removing the conditions and clean them up. Reattach and tighten up well.
I did jump the solenoid before I changed it. It just clicked once.
 

manicmechanic007

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1992MustangGT,
The click means the ignition switch is working
you jumped the fender apron solenoid and nothing (or just click) means
You need a starter solenoid on the starter (or a starter)
Pull it off and bench test it or have CheckerPepZone test it for you
I would replace the starter as an assembly not just the solenoid
The test is to verify battery voltage at the starter solenoid small wire needs more than 10.6 v to pull in
Check the grounds before you replace anything
Bench test Your starter with some jumper cables and a good battery
 
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manicmechanic007

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Your car is getting old enough that you might want to check some of the wires for voltage drop
That's why I mentioned 10.6v at the starter
That is a minimum voltage to pull in the starter solenoid and then make the starter spin
If the wires have what they call negative voltage drop means
The 12.x voltage at the battery will only be 10 or so at the starter
Means then if all the parts are good it still will not crank
What I see on vehicles with this trouble is hard brittle wiring
That's when you want to ohm out the wires and replace if necessary
 
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KRUISR

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When ever I get just the click, it has always been not enough voltage. Usually bad connections (power or ground) or low battery. Another quick test for starter solenoid would be to disconnect wire from starter solenoid to starter and touch it directly to the positive battery terminal - obviously only do this after you put it in neutral and then double checked it is in neutral again. If starter okay, it should crank. If key is ON it should start.

To test if you have bad engine ground, take a set of booster cables and get a good connection from an engine bolt to chassis bolt (negative battery post would work too.
 
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Thank you everyone for the suggestions & advice. I will take your advice and do some testing, hopefully tomorrow. There's 16" of snow on the ground and it's cold as hell right now. So this might be a challenge, but I got to get this figured out ASAP. I'll keep you posted. Thanks again guys....
 
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mikestang63

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couple of things i will add

1. it is super important your battery has a full charge
2, check all of your grounds - they should be clean and tight
3, check your battery cables - are they tight not frayed or old and brittle
4. make sure the starter solenoid has a good ground to the fenderwell. it is actually grounded by the backing plate and the bolts. Make sure the area where it bots up is tight. You can also add a small 10 gauge jumper wire from one of the mounting bolts directly to the battery ground terminal.
5. IMO only get a FOMOCO starter solenoid as the parts store ones are crap and are often dead out of the box and do not last long.
6. tap on the solenoid with the back of a screwdriver a few times. They fail because the plunger inside often sticks or gets fused together. If you rap on it a few times that may free it up. Not a fix but will confirm it is faulty.

IMO this would be a perfect time to swap out the factory starter as well to a 93 mini starter. Much less amp load on the system and a very easy install.
 
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Ok guys, here's an update......I think I had two problems and I got one of them solved today. So here's everything I did today......

I tested the battery with my battery tester and it was fine. I then cleaned the ground to the block and the wire terminals (which was fine to begin with, but I cleaned them anyway). Tried to start it with the key and all I got was 1 click. So then I jumped the small ignition post on the starter solenoid to the large battery post on the solenoid and it just clicked 1 time. Since that didn't work, then I jumped across the two large posts on the starter solenoid and again, just 1 click.

So after doing all this I assumed the problem was a bad starter. So I went to Autozone and bought a new starter and installed it. Then I tried to start it with the key and again, just one click. Then I jumped the ignition post on the starter solenoid to the large battery post on the solenoid and again, just one click. Then I jumped across the two large posts on the solenoid and it started!!!! So I let it run for a while to warm everything up, then I shut it off and hit the key again to see if it would start and again, just one click.

So is this brand new solenoid I just installed the other day a bad solenoid? Or is there another issue? It doesn't seem to be a low voltage issue or a ground issue. And the ignition switch is brand new (just replaced it this past summer). I'm stumped.....
 

Mustang5L5

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Whe you apply power to the small post, it closes the relay and connects the two larger power posts together to send power from one side to the starter cable.

You can test continuity when you activate the small post to see if the relay is closing and holding.

Another possibility is that the bad connections are the connections on the starter relay itself. Jumping across the two large posts could simply be bypassing the bad connection. You might want to remove and clean ip all those connections with sandpaper and reassemble.
 
Whe you apply power to the small post, it closes the relay and connects the two larger power posts together to send power from one side to the starter cable.

You can test continuity when you activate the small post to see if the relay is closing and holding.

Another possibility is that the bad connections are the connections on the starter relay itself. Jumping across the two large posts could simply be bypassing the bad connection. You might want to remove and clean ip all those connections with sandpaper and reassemble.
I will try that (I assume you're talking about cleaning the terminals on the wires). I also still have my old solenoid, so I think I might try reinstalling it and see what happens. It might tell me if the new solenoid is bad or not.
 
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Try jumping from battery + to the small post on starter solenoid. If solenoid is good it should crank.
I'll try that too.

Question.....the positive battery cable from the battery connects to the large post on the solenoid, which is where I jumped the small ignition terminal from. How would jumping it straight from the battery as opposed to the large post on the solenoid make any difference? Isn't that basically the same thing? Not arguing, just trying to understand the difference since the large post connects directly to the battery via the battery cable.