My car started reading low voltage off and on after my header install about three weeks ago. Since there was no issue I figured it was just one of those tricky quirks you get sometimes. Since then there has been no real issue however the other morning I went out and car would not start.

Pulled the battery and went to Autozone. Got it charged and checked, it was good which means that the alternator probably has an issue.

So the battery is good. I decide to drive the car to the airport 70 miles away As I drive I see the voltage steadily going down and finally about 10 miles from the airport the gauges go dead, ABS and TCS warning flash and basically the battery is at 6-7 volts. As I pull up on the offramp to the airport and the engine hits higher RPM as I downshift the volt meter jumps back up to 12-13 and all seems good as I park the car.

I come back three days later, get in, it barely turns over and starts but the low voltage, TCS, ABS lights come on almost immediately. It is night so I have to use the headlights. By the time I get from the inside parking lot to the outside lot the guages go dead and the healights are very dim. I pull into a space, turn it off and the car is dead (only clicks when turned over). I have to have the car towed 72 miles home and it sits out back dead right now.

First question, what is the order I should check out possible causes? I am pretty sure I got the ground loop straps connected back correctly after header installation but maybe there is something I dont know about?

Second question, I have heard that some places can rebuild your alternator and make it better (stronger, etc). Who would do that?

Third I can get a new alternator from Autozone for $149 or can buy a used OEM for $12x.00 with 40k miles on it. Which should I go for?

If you have any knowledge on any of these issues please help me out. Thanks

Cajun

 

I'd get the alternator checked. Depending on mileage you could have stuck or worn brushes. Its obvious its not charging and you may not have field exitation voltage. That can be a connection or internal.

 

look for some posts in the archive by Evil-Twin search on alternator.
Bill is a retired GM engineer and made a number of posts on the topic.
Bascially the C5 is quirky and needs a specific alternator. Many replacement ones will not work.. If I remember it has to do with the system checking the resistance of the alternator.... if you do not buy a replacement with the same resistance it will not work...

You are better to have yours rebuilt.

Look for auto electric shops, generators, alternators in your local yellow pages

 

Before you get too far out in alternator replacement territory, I would check everything in the alternator charging & starting circuit. Start at the battery, inspect & clean the terminals. They must be torqued to 11 ft/lbs to be properly connected. Check the battery connections at the starter and on the back of the alternator. Check the Ground cable and ground connection on the passengers side of the engine block down near the starter. Theres a connector on top of the alternator, Check the wires and connector for a proper/clean connection. Read the output of the alternator with a digital volt meter (at the battery and on the main output of the alternator (big screw on the back with the red wire). They should read the same.

Check all of that stuff out before you have the alternator replaced or rebuilt.

BC

 

Bill knows of what he speaks...
I had a no start after my header self- install.... Bill helped me find the problem.

I had missed one of the ground wires that was supposed to connect to the ground on the passenger side of the block above the starter.

Did you do the header install yourself?
Did you have to disconnect the ground wring on either side of the block?
Did you have to disconnect the wiring to the starter?
It may be that those terminals are not clean or properly torqued.

 

Thank you so much Bill, I will go through these steps today. I know the battery is good to go since I had it charged and tested on Saturday. Again thank you!!!!!!!!!!!

 

The other thing to check is the wiring on the passenger side of the engine. If you installed headers and started having this problem shortly afterwards then the wiring may be to close to the header or even touching it and there are a couple of threads out there where people have found the wiring burned or melted around the passenger side header.

 

OUTSTANDING additional info! I didnt think about that. Ill have to remember that. That would be the starter wires and the one red wire going to the alternator!!!

BC

 

Alright so the good............and bad news is that the alternator is good. Now I am at a loss. I have checked all connections to the battery, the alternator. I do not see any burnt wiring and this issue took three weeks to get to this point............would it take that long for a wire to burn?

I am really starting to get worried here because the car is doing crazy stuff. I can hear a clicking on and off when I have the hood up and then the light in the engine bay will get dim as the battery drains. It will lock/unlock over and over again.

Then when I shut it off the security light kept blinking and the dinging sound would not stop even with all doors and hatch shut.

Bill I will PM you to see if you can give me anymore guidance so I can try to get this fixed. I have to drive this car from NY to NC in three weeks because the Army is moving me. I have to get this fixed and quickly.

Cajun

 

One more thing, I jumped the battery to start the car and when I shut it off and tried to start it again in just clicked really fast.....does this mean a starter issue or is it just because the battery does not have enough power to turn the starter? Thanks

Cajun

 

So,,,,,,,,,,,,,,,,your in the Army!!! Well, that gets you some extra special treatment! I just PM;ed you my cell# Call me!

BC

 

Bill - What an OUTSTANDING thing for you to do, I applaude you !