Car Charging System Issue

Merrifast · Dec 24, 2011

Hi everyone, I am a probationary member so I am posting this question here in hopes someone will find it.

First off I would like to state that I just bought my car one week ago, and I have already put a new alternator and battery in the car.

The problem is that the car will fail to start on some key turns, and on others will fire right up. When it does fail to start i can hear a hissing sound coming from the middle console (near where the ECU is located... could be the ECU itself). While driving the car on a full battery lights are strong, CEL lights are strong. while driving on half full battery lights are dim most of the time, but then sometimes will become strong for a few minutes then go back to dim. This indicates to me that the charging system is intermittently working. While driving on a near empty battery every CEL light will come on, car will try to die unless I drive WOT, or try to hit potholes, then the charging system will kick in for a few minutes. I am aware that all CEL lights being on indicates that the ECU does not have enough power, and car will die, as it did.

All of these seem like symptoms of a bad ground. I have bought new ground cable to be installed tonight (Christmas Eve), also I have noticed that the 10 gauge (i believe it is 10 gauge, if I am wrong please let me know) wire that from the battery to the fuse box seemed to be slightly burned as picture below indicates:

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I then proceeded to take apart the fuse box to investigate if any of the other wires appeared to have burns. After fuse box bottom case was off I noticed another weird wiring issue, however I am not sure if this is STOCK: there is a 14-or-so gauge wire coming off of the main 10 gauge power wire (from the battery) that goes to one end of the AC Fan. Should this AC fan be getting power directly from battery, if this is not normal please advise where this lead should come from? Here is a picture of the wire:

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If I cannot find a gremlin in the wiring, I will resort to buying a new ECU.

I appreciate the forum, and wish everyone a Merry Christmas!

-Alex

Anubis_4_99 · Dec 24, 2011

I can't help with your problem, but your post can be posted in the newbie section under "maintenance and repair" where it belongs.

That's where all newbies are supposed to make there posts until they become full members.

Good luck with your problem though, hopefully someone can chime in and help out, i'm having to deal with my own electrical gremlin as well.

D3monX · Dec 24, 2011

i reported your post so hopefully a MOD will move it to the correct section and you can get your answers, also it looks like one of your wire in the first picture is corroded which can cause your problems just like that burnt wire, and also have your actually tested your alternator because your battery shouldnt be dieing so quickly and your should also go to autozone or your auto parts store so they can hook up an OBD2 reader to see what CEL are popping up.

Merrifast · Dec 24, 2011

Thanks for moving the post to the correct section.

I will post progress when I get the 10 gauge white wire that goes from the battery to the fuse box, and the new ground cable replaced. Going to my grandpa's tomorrow to pick up my 10 gauge wire spool.

Thanks,
-Alex

P.S. I need 30 posts, or be active for 30 days to be a regular member right?

D3monX · Dec 25, 2011

you need both 30 post and 30 days

Merrifast · Dec 26, 2011

I replaced the old Ground Cable which runs from the firewall to the Ground Terminal on the Battery, and then down to the transmission with a new Ground Cable, and Battery Terminal. I also replaced the 4 Ten Gauge Wires that run from the Positive Terminal of the Battery down to the 100 amp fuse on the Fuse Box.

* I did not re-test the alternator.

As soon as I fired up the car (I had to jump it) the battery voltage read 9.5 volts. The battery voltage dropped rapidly, and did not go up at all. I finally shut off the car about a minute later when the voltage was down to 8.5 volts. Car obviously will not start back up, and is in need of a battery charge so I don't fry the battery. I will be picking up a battery charger from my grandpa tomorrow.

While turning the key to the "Start Position", about 50% of the time I will hear a whining / hissing sound coming from under the center console which I believe is the ECU, but may be something else, not sure what else it could be though. When I hear the whining / hissing sound, the car will not even try to fire. However, if I retry there is about 50% chance that the starter will turn the car over. Car starts right up if this happens. Not sure if I have a bad ECU or just a bad gremlin.

If anyone has any insight / past experiences I would greatly appreciate them. I am one step away from locating a new wiring harness, fuse box, and ECU. Should I replace the wiring harness, ECU, and Fuse Box, or try to fix what I currently have? I could have a bad ground still, but I am not sure where all of the grounds are.

Thanks in advance for any information.

-Alex

supermario300hp · Dec 26, 2011

just had a similar issue. changed the alternator and the same problem was still there. ended up being a bad ground, check everywhere. anything that was touched or altered check and double check, thats the best advice i can give.hope all goes well.

talonspeed21 · Dec 27, 2011

The noise sound that you hear in the center console might be the MPI relay which is located close to the ECU. there are multiple things that can cause a battery drain. Here are some things to check
Battery (you replaced)
Alternator (you replaced)
Ground Wires
100 Amp fuse in the fuse box to the Alternator
the wiring harness for the charging system.
MPI replay
Have the alternator tested. I have seen cases where people have purchased new remanufactured alternators and they didnt work.
Hope that helps.

Merrifast · Dec 27, 2011

Thanks for a list of possibilities.

I will be checking each of these this week, and give feedback.

gofer · Dec 27, 2011

Try these...

Finding bad grounds
Finding a short, partial short, or battery drain

Merrifast · Dec 29, 2011

I took the alternator back to Autozone today, it failed the diode and another test (i forget what other test), but it failed 2 out of 3 tests. They said they will replace the alternator free of charge. I will pick it up tomorrow and give it a try, however I have a sneaky suspicion that the car is killing alternators since the one that was on it when I bought the car looked brand new as well. Is it possible that the car is frying alternators? I have not seen any arching from the alternator to the body or block occurring, but it still may have done so.

Thanks for all of your help, I will keep you posted if the alternator fixes the issue or not. I still will need to fix the hissing / whining sound from under the center of the dash, but this is a start.

-Alex

talonspeed21 · Jan 1, 2012

The alternator could be grounding out on your intercooler piping...if you have a short route setup that runs close to the alternator. Excessive heat can also cause alternators to fail early but thats normally over some time. Those are the only two ways that i can think off that could kill your alternator.

YES · Jan 1, 2012

Heres a test to see wheather you have a bad battery, bad alternator or bad connections to the charging system.

1. Get your battery charged at autozone and ask if its still good, if its still good install it on the car.

2. Buy a voltmeter from walmart, I got mine for $12

3. With car off check your battery voltage with voltmeter by doing this.......set voltmeter to DC voltage......there will be numbers in there from like 20-200........set it to 20. Install the positive and negative to the voltmeter like they should go.....negative lead to where it says COM.......positive lead to DC. Now connect positive lead to positive battery terminal and negative lead to negative battery terminal. Your readings should be between 12v-13v

4. Turn your car on and keep it running. Now do the same test on the battery and the numbers should be reading higher like 13v to over 14v. Test it every 2 minutes like 3 times and see if the numbers stay the same or if they go down.

GET BACK WITH YOUR RESULTS!!!!!!!!!!!

ps. sometimes when you buy a new battery or alternator they might come bad from store so always test them first and keep your receipt

awdspyder98 · Jan 1, 2012

I had purchased a new alt. And tested it at the store before I walked out... Guess what.. it failed. I also added a few ground straps just for added protection and I haven't had a issue since.

SpiderGST · Jan 1, 2012

I've actually had about 3 alternators rattle apart on me. I just put red gel lock tight on the casing bolts seems to be working so far.

xxNocturnalxx · Jan 1, 2012

It's an alt. Issue, the remans are complete junk, just keep returning them til you get one that actually works in your car.

zonerdck · Jan 1, 2012

To check to see if you have a solid connection to the battery you can take your meter and put one end on the case of the alternator and the other to the output stud on the back of the alternator. If you get a good 14.3 volt reading or so here but not at the battery then you know that somewhere in between is the problem. Whether it be the grounding of the alternator or the wires going to the battery.

You can then change the setting on your meter to resistance and put one probe on the positive battery terminal and the other to the end of the main power wire that attaches to the alternator. It should read very low like .00 to .05 ohms of resistance.

You can then do the same with the ground post of the battery and the case of the alternator.

If any of these don't check out there is an issue otherwise the issue is somewhere else.

P.S. Make sure when you use your probes on the battery posts that you go to the actual lead post versus the terminal itself as this will help find any bad connections on the terminals.

Merrifast · Jan 2, 2012

Thanks Zonerdck, I did not realize you could ground on the Alternator Casing.

I will do both the resistance test and the alternator test from the alternate case/power terminal when I get the new alternator installed.

Friday I was working on the oil pan gasket until 12:00pm, Saturday I was pulling a 6bolt motor and 1g awd tranny at the junkyard (everyone was pissed because I found it), and Yesterday I was too hung over to do anything at all. Today should be the day of results.

Thanks All,
-Alex

PS: Happy New Year!

Merrifast · Jan 7, 2012

I just replaced the oil pan gasket and alternator. Car seems to be charging now, however the issue with the hissing sound commingle from under the dash in the center console remains. I unplugged the mfi relay and it still is having troubles starting. It will only start about 10 percent of the time I turn key. What else could this be?

Sent from my android please excuse typos.
-alex

I meant to say it still makes the hissing sound when I unplugged the mfi relay. I plugged it back in though.

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