New Car Charging issues HELP

[bdazzgt]

ok here is the deal i have a 90 GT that i just got back together. I drove it to my dads house which was about 20 miles just fine. I go and start it today and the volt gage barely moves it is on the second notch above 8, well i keep driving from my dads house to my sisters 30 miles. I figured the gauge wasnt working. Well i get to my sisters house and i go to start it and it does nothing click click click. I get a roll start and my Volt Gauge comes alive it starts chargin 13-14 volts -the middle of the gauge well i get home and it starts fine. I then go out and move my car and the gauge isnt work again but it seems to start fine, what is the deal here? Did i drive 30 miles on battery? Now before you guys try and explain about the alternator wiring, i have a "selfcontained" harness i dont have any chassis wires going to the alternator There are two plugs and they are connected together where they should be then the green/red wire is going to a wire that is hot when the key is on. Then i have a 4G wire going to the battery. What gives here, i know it is all the stuff is good i just pulled out of my old car and put it in here. i just would like to know what is going on. Thanks-James .....i hope i explained everything well

 

[86bluecobra]

I guess your first step would be to see if your alt is catually putting out. The main bolt (for lack of a better word) that the 4G wire hooks to could be loose. It was in my case and my car was doing the exact thing you are describing. Tightened it up and no more charging issue. Some times after a long ride my car would charge sometimes it wouldn't. Guess it wasn't contacting very well.

 

[bdazzgt]

i will go check it now....just checked it....tight as a virgin on prom night

 

[jrichker]

Make sure that the green wire has 12 volts on it when the switch is in the run position.

 

[bdazzgt]

ok i will go check it now, it has 12 volts when the key is on, i just spliced it into one of the TAB/tad silenoids red wire. It died on me at work this morning and wouldnt start so after work my buddy gave me a jump start, the volt gauge jumped up to the middle, i drove it all around for about 2 hours. After that i went to walmart and shut it off. I run right in and come back quick i go to start it up and the gauge doesnt move, the same thing it was doing before. What could this be??? i am stumped i thought it was a bad ground but i fixed it so i dont know what it is...

 

[HISSIN50]

I'm with JR - either it's not switching on (bad wiring connection - it might be IR sensitive) or the alt itself is not exciting for some reason.

I'd triple check that wire (especially when the alt decides not to charge) and if that's ok, make sure your charge cable connections are ok. Loose connections tend to make a real voltmeter jump all over the place but a bad connection will do nothing.

Then the alt is left.

Good luck.

 

[bdazzgt]

Thank God for you guys chiming in, I blew off a radiator hose and it sprayed antifreeze everywhere would this cause the alternator to go bad. I know they are exposed to moisture, but this went all over the place because it hit the fan. How would i see if the alternator is charging besides the gauge? i have a multimeter, but i dont know exactly what to do to check it if you could give me a step by step details i would appreaciate it. Thanks -James

Also what does this mean? (bad wiring connection - it might be IR sensitive)<---dont understand that. And the alternator will charge for a while but after i shut the car off every once in a while it will quit charging, I also checked all of the connections and they are tight.

 

[bdazzgt]

Could the battery be bad also and give a false reading?

 

[bdazzgt]

i went and unhooked the battery for about 20 minutes. I hooked the battery back up and it charges now....what gives???? Is the battery bad? Maybe the ground on the negative terminal? I am lost and need help on this. Also i found out there was a viper alarm system in the car which i dont have any of the stuff for so i am going to take it out, Could this cause the problem? Would a short cause these problems maybe a loose wire? I am grasping for straws right now.

 

[HISSIN50]

Chances are that the alternator or alt wiring is the issue - I've not seen a battery cause an issue like that (which is not to say others have seen it).

When it goes to crap, put your meter (set to the 20 amp DC volts scale) on the alternator's charge stud (red lead to the charge stud, black lead to a bolt on the motor). You should see above 12.6 volts with the car idling. Now do the same thing at the battery (with the car idling). If both are the same or very close, and under 12.6 volts, chances are that you're running off the battery.

At that point, I would check the wire JR mentioned. See if it shows 12 volts. If not, you found the (or one) issue.

If you find that you have decent voltage at the alternator but not at the battery, go along your 4 AWG cable and check it at the connections (e.g., for my set-up, I'd check each terminal at my ANL fuse and the connection at the starter solenoid's battery lug). A bad connection would allow the alternator to put out but the current would not reach the battery.

The IR comment was just a reference to a loose or bad (Dirty, etc) connection acting up when it gets hot (resistance causes heat, heat causes more resistance, and it snowballs).

I'm sure JR will have some eloquent thoughts as well (his posts are a LOT easier to decipher than mine).

The hose blowing could definitely have caused some damage or issues. But as to whether that's it or not, who knows (we need to get that 'who' guy to post on here - he seems to know a lot of things that most of us don't ).

Good luck.

 

[HISSIN50]

i went and unhooked the battery for about 20 minutes. I hooked the battery back up and it charges now....what gives???? Is the battery bad? Maybe the ground on the negative terminal? I am lost and need help on this. Also i found out there was a viper alarm system in the car which i dont have any of the stuff for so i am going to take it out, Could this cause the problem? Would a short cause these problems maybe a loose wire? I am grasping for straws right now.

Intermittant issues blow. You really need to wait for the car to act up (start up and have the voltmeter be dead. Immediately perform diagnostics) or a lot of the testing is invalid.

I would not look at the old alarm as being an issue. The alternator circuit can largely be thought of as a stand-alone system, and an alarm would not cause an issue that I can imagine. I'd wait on doing the alarm removal till this is fixed - introducing more variables makes diagnostics harder (you could end up with a no crank situation after the removal, and you have that sometimes right now).

Good luck.

 

[bdazzgt]

I just went out checked it while the alternator is charging according to the gauge. It was about 13.5ish at idle with my 130A alternator. I dont know when it will stop charging again. When it does i will check. The battery also had the same amount of volts 13+ Would a short cause these problems, to me they sound like a loose wire.

 

[bdazzgt]

My airbag light keeps blinking would this have anything to do with it?

 

[HISSIN50]

Air bag light would likely not be related. If you only had dead batteries, that would be cause to go short hunting. But I think you noted that the voltmeter reads low after jumping the car (the alt should be putting out 14.4+ volts at that time), so it still sounds charge related.

I don't know about fox airbags but maybe the light flashing is from the battery going dead (in case the diagnostics monitor's capacitors become discharged).

See S&2B's site for airbag diagnostics:

http://www.veryuseful.com/mustang/tech/airBag/airBag90-91.html

Good luck.

 

[jrichker]

The crimp on lugs can sometimes be a problem if they are exposed to oil or other fluids. I had a Cessna Cardinal with an intermittant no crank condition that I couldn't find. One morning it refused to crank while it was parked in the hanger. I pulled the engine cowling off and started to inspect the wiring while my helper worked the switches. I grabbed the power wire lug crimped on the starter and burned my hand. It was hot because oil had seeped into the crimped lug and made a high reistance connection.

Here's how to check the connections for high resistance.

A voltmeter is handy if you are familiar with how to use it to find bad connections. Measure the voltage drop across a connection: more than .5 volts across a connection indicates a problem.
See http://www.fluke.com/application_notes/automotive/circuit.asp?AGID=1&SID=103 for help

 

[bdazzgt]

Thanks Jr and Hissin i will go and explore this morning, i just got that alarm pulled out and there were several loose wires on the ignition column and a few hanging out just exposed so i took it out, it seems to charge and run fine now, hopefully i can get this figured out.

 

[bdazzgt]

my console was getting hot to the touch. I took it out and the hot wire to the cigarette lighter was touching the ashtray, would this cause some problems with the charging system?