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Discussion Starter #1
have a starting problem.
battery reads 12.45 volts and is two years old.
battery terminals look good and tight, cables look fine. car has a good ground.
car will not crank on its own, or tries to crank very slow. starter solenoid kicking and holding good.
put jumper cables on the battery and starter still will not spin the engine over, but just cranks
it slow.
any ideas?
 

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Yes. Connections "looking" good and tight do not mean that they ARE clean and tight. Disconnect and clean them with a battery terminal brush, both the posts and the clamps. Inspect for corrosion where the cables meet the clamps.

And have someone monitor the voltage with a voltmeter (preferably digital) while you crank. If it drops below 10V, the battery is bad or the starter wiring is shorting out. Open-circuit voltage doesn't tell the whole story, there is no load when measuring that.

Was this sudden or has it been coming on for awhile?
 

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Discussion Starter #3
Bob Lincoln said:
Yes. Connections "looking" good and tight do not mean that they ARE clean and tight. Disconnect and clean them with a battery terminal brush, both the posts and the clamps. Inspect for corrosion where the cables meet the clamps.

And have someone monitor the voltage with a voltmeter (preferably digital) while you crank. If it drops below 10V, the battery is bad or the starter wiring is shorting out. Open-circuit voltage doesn't tell the whole story, there is no load when measuring that.

Was this sudden or has it been coming on for awhile?
think it's been going on for a bit, but I just got involved. terminals on the battery were clean, but I brushed them and got them back on tight. just odd that the car won't try to start even with jumper cables hooked to my running car.
 

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Jumper cables have to flow through the post/clamp connection, so if that is dirty, jumper cables and external battery won't help. Seen it happen before.

Try the voltage drop test while cranking, also. If it stays above about 10.5V when cranking, the battery is good, or good enough to start.
 

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Discussion Starter #5
Bob Lincoln said:
Jumper cables have to flow through the post/clamp connection, so if that is dirty, jumper cables and external battery won't help. Seen it happen before.

Try the voltage drop test while cranking, also. If it stays above about 10.5V when cranking, the battery is good, or good enough to start.
OK, will check voltage drop next.
 

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Technically, an inline amperage test is called for, but it's very unlikely that any given hobbyist has an ammeter capable of handling cranking-amps without blowing a fuse.

I just fixed a problem like this with my truck, and in my case it turned out that my positive battery cable was messed up. I could see a bad ground from the engine or transmission causing a problem as well, or any other connection issue that doesn't let high current flow freely.

The service manual that I have for that truck called for an inline amperage test, but I do not own a meter capable of handing that current, and from what I can tell, a meter capable of measuring that amperage is very expensive.
 

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Discussion Starter #7
TWX said:
Technically, an inline amperage test is called for, but it's very unlikely that any given hobbyist has an ammeter capable of handling cranking-amps without blowing a fuse.

I just fixed a problem like this with my truck, and in my case it turned out that my positive battery cable was messed up. I could see a bad ground from the engine or transmission causing a problem as well, or any other connection issue that doesn't let high current flow freely.

The service manual that I have for that truck called for an inline amperage test, but I do not own a meter capable of handing that current, and from what I can tell, a meter capable of measuring that amperage is very expensive.
ya, most likely made by Fluke.
I have a fluke, but only good for 100 Amp. I'm an electrician. IBEW inside wireman. more comfortable installing an 800 Amp service panel than automotive wiring. one thing about cars and all wireing is the ground. most important. need a good return path.
i'm just getting the feeling with this car that the starter is done - and pulling way too much current when it tries to crank.
going to check the cables one more time and then pull that starter and get it tested at autozone.

side note: had a Ford explore once. thought the starter was bad. changed it at $150 and same problem.
turns out my year had a silent recall. bad pos battery cable, they push the wire into the battery terminal and then push a "stake" through to hit the cable. the stake missed. the cable and terminal became loose over time. bad connection. and makes you think its the starter.
this isn't my car so I don't want to just start swapping out parts. owner dosn't have much money, so i'm tring to do this the most painless way. LOL

i'm working on a 99 olds minivan, but it's set up the same as most cars, like my 2000 Voyager or 92 Lebaron.
same principals, bit different looking parts.
 

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Connect a jumper from the positive battery terminal to the terminal on the starter where the positive battery cable connects. Probably safest to connect the starter-side first. DO NOT connect to the solenoid side at the starter.

That should bypass the positive battery cable entirely, as far as the starter is concerned.

Try the key.
 

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Bob Lincoln said:
Yes. Connections "looking" good and tight do not mean that they ARE clean and tight.
+1 to this. The Imperial got a full battery cable re-wire last fall after it started draining a brand new battery whenever the car was left alone for two days. Had no parasitic draws to explain it. Cleaning the battery terminals did nothing.

Turned out to be due to corrosion in the power distribution center where the positive battery cable attached. The alternator simply couldn't charge the battery. I also found corrosion inside the wire insulation down by the starter motor. So, I went and got a healthy amount of 4 gauge welding cable, some brand new ring terminals, and rewired everything that came and went from the battery. The starter doesn't just crank now, it cranks like its life depended on it. "Yes, sir, I'll get it done right now, sir, please don't replace me." The car starts faster. And the voltage gauge on the dash pretty much stays nailed to one spot - barely ever moves now.

Moral of the story... even if the wires and connections look good, they may not be.
 

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That's similar to my pickup, the negative cable was corroded from the battery terminal about 2" in. I ended up having just enough slack to cut it off and screw it into another battery terminal.

My truck uses thicker cable, like 1 or 0 gauge. It's a foreign truck though, so no idea if the difference is just overkill or not.


Because the afflicted vehicle is an Oldsmobile I'm going to move this to the non-Mopar area.
 

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You guys are inspiring me, our minivan starter has gotten slow ... though in our case it probably IS the battery. It's an old battery and we've run it down to zero a couple of times (can't leave anything unlocked, kids get in and rifle through it and leave the door open when they're done.)
 

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I hope that it's the battery Dave, cause repairing otherwise is a royal PITA.
 
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