Engine Starting Issue

1989LXFOX

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Jan 19, 2018
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Hello all,

I hope everyone is staying healthy and safe! I recently posted a thread about questions about an alternator fitment. Is it possible for a one year old battery to be so dead that it cannot be jumped? I thought i was having alternator issues, but now I am not sure that the issues I was having are related to my alternator (was upgraded to a 100amp by a previous owner).
While I am not ruling out the alternator, I tried to jump my car after it had sat in my unheated garage for the last 6-7 months and I couldnt get it started. I let it sit for a while too. At first I would get clicks, then all power left. Then after leaving it for a while, I would get a very slow chug chug then nothing, I even had someone in the other car reving the engine. I was getting the battery to about 11.6 volts
My questions are:
1. Can a battery to be to dead to jump?
2. The car should start, even with a bad alternator right?
3. I realize this may be the starter, but shouldnt I be able to even jump the car?

I am trying to figure out if I need a new battery as well as everything else. The battery in there is only about a year old. Initially I thought that I needed a new alternator because it wouldnt start on it own. I was able to jump it to get it started last time I drove it (about 6-7 months)

Thanks in advance
 
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General karthief

wonder how much it would cost to ship you a pair
Mod Dude
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Yes it could be your battery has an internal short. Don't keep trying to start it with the battery not fully charged or if it cranks slow when you jump it, that will kill a starter.
 
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1989LXFOX

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Yes it could be your battery has an internal short. Don't keep trying to start it with the battery not fully charged or if it cranks slow when you jump it, that will kill a starter.
Thanks Karthief! Can I take a battery out of my Rav4 and drop it in temporarily to see if it starts? I read online that swapping different batteries can be bad for your car. The battery is relatively new (about 1 year) and didnt get much use. I was thinking that since it sat for so long in the cold that it be killed. I am just confused why the car wouldnt start even while being jumped.
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
19,713
6,590
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polk county florida
Yes you can try the rav4 battery.
While you are in there check and clean all battery related cables.
Batteries have different cranking amps, the problems with batteries is mostly from usage, charging system capability and connections along with cable size. All this has to work together.
DISCLAIMER: the information given is not based on any actual mechanical experience and should be used with caution,
 
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jrichker

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Thanks Karthief! Can I take a battery out of my Rav4 and drop it in temporarily to see if it starts? I read online that swapping different batteries can be bad for your car. The battery is relatively new (about 1 year) and didnt get much use. I was thinking that since it sat for so long in the cold that it be killed. I am just confused why the car wouldnt start even while being jumped.

No Crank checklist for 5.0 Mustangs

Revised 24-Oct-2013 to update voltage drop figures.

No crank, slow crank and stuck starter solenoid problems have the same root causes – low battery voltage and poor connections. For that reason, they are grouped together.
Use the same initial group of tests to find the root cause of slow crank, no crank and stuck solenoid problems.

Since some of the tests will bypass the safety interlocks, make sure that the car is in neutral and the parking brake is set. Becoming a pancake isn’t part of the repair process…


1.) Will the car start if it is jumped? Then clean battery terminals and check battery for low charge and dead cells. A good battery will measure 12-13 volts at full charge with the ignition switch in the Run position but without the engine running.
A voltmeter placed across the battery terminals should show a minimum of 9.5-10 volts when the ignition switch is turned to the Start position and the starter engages or tries to engage. Less than this will result in a clicking solenoid, or slow cranking (if it cranks at all) or a starter solenoid that sticks and welds the contacts together.

Most auto parts stores will check your battery for free. It does not have to be installed in the car to have it checked; you can carry it with you to the auto parts store.

The battery posts and inside of the battery post terminals should be scraped clean with a knife or battery post cleaner tool. This little trick will fix a surprising number of no start problems.

The clamp on with 2 bolts battery terminal ends are a known problem causer. Any place you see green on a copper wire is corrosion. Corrosion gets in the clamped joint and works its way up the wire under the insulation. Corroded connections do not conduct electricity well. Avoid them like the plague...

If the starter solenoid welds the contacts, then the starter will attempt to run anytime there is power in the battery. The cables and solenoid will get very hot, and may even start smoking. The temporary fix for a welded starter solenoid is to disconnect the battery and smack the back of the solenoid housing a sharp blow with a hammer. This may cause the contacts to unstick and work normally for a while.


A voltmeter is handy if you are familiar with how to use it to find bad connections. Measure the voltage drop across a connection while trying to start the car: more than .25 volts across a connection indicates a problem. The voltage drop tests need to be done while cranking the engine. It's the current flowing through a connection or wire that causes the voltage drop.

See http://assets.fluke.com/appnotes/automotive/beatbook.pdf for help for help troubleshooting voltage drops across connections and components. .

attachments\64167


Voltage drops should not exceed the following:
200 mV Wire or cable
300 mV Switch or solenoid
100 mV Ground
0.0V Connections
A voltage drop lower that spec is always acceptable.

2.) Check the battery to engine block ground down near the oil filter, and the ground behind the engine to the firewall. All grounds should be clean and shiny. Use some sandpaper to clean them up.

3.) Jump the big terminals on the starter solenoid next to the battery with a screwdriver - watch out for the sparks! If the engine cranks, the starter and power wiring is good. The starter relay is also known as a starter solenoid.

The rest of the tech note only concerns no crank problems. If your problem was a stuck solenoid, go back to step 1.

4.) Then pull the small push on connector (small red/blue wire) off the starter solenoid (Looks like it is stuck on a screw). Then jump between the screw and the terminal that is connected to the battery. If it cranks, the relay is good and your problem is in the rest of the circuit.

5.) Remember to check the ignition switch, neutral safety switch on auto trans and the clutch safety switch on manual trans cars. If they are good, then you have wiring problems.

Typical start circuit...
Diagram courtesy of Tmoss & Stang&2birds
attachments\21328


6.) Pull the starter and take it to AutoZone or Pep Boys and have them test it. Starter fails test, then replace it. If you got this far, the starter is probably bad.


Starter solenoid wiring for 86-91 Mustang
attachments\52294



Starter solenoid wiring 92-93 Mustang or earlier Mustang with upgraded high torque mini starter.
[
attachments\53216


Electrical checks for the switches and starter solenoid

Remove the small red/blue wire from the starter solenoid. Use a screwdriver to bridge the connection from the battery positive connection on the starter solenoid to the small screw where the red/blue wire was connected. The starter should crank the engine. If it does not, the starter solenoid is defective or the battery lacks sufficient charge to crank the engine.

If the starter does crank the engine, the problem is in the clutch safety circuit (5 speed) or Neutral Sense Switch (auto trans) or ignition switch.


See the Typical start circuit diagram above for wiring information for troubleshooting.

You will need a voltmeter or test lamp for the rest of the checks. Connect one lead of the voltmeter or test lamp to ground. The other lead will connect to the item under test.
Look for 12 volts on the white/pink wire when the ignition switch is turned to the Start position. Check the ignition switch first.
No 12 volts, replace the ignition switch.

The next step will require you to push the clutch pedal to the floor (5 speed) or put the transmission in neutral (auto trans) while the ignition switch is turned to the Start position.
Good 12 volts, check the clutch safety switch (5 speed) or Neutral Sense Switch (auto trans) for good 12 volts on both sides of the switches. No 12 volts on both sides of the switch and the switches are defective or out of adjustment. Check the wiring for bad connections while you are at it.
 
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