Please help with the following issue if you can:

First of all my car is a 1998 3.0 CL with all stock options, no accessories.

On 8/31/07 while driving home my battery light came to a steady ON state. National Tire & Battery said the alternator was gone. They replaced it and on the next day (9/1/07) the battery light would come on for 1 or 2 seconds then go off. This would happen every 10 minutes of so. I brought the car back to NTB and they verified that the new ALT was still good, and they replaced the battery because it was not holding a charge. The next day (9/2/07) the batery light occasionaly comes (less frequent than the previous day) on for just a second then stays off for a while, then will randomly go on and off for 1 second.

Now that I replaced both the battery and alternator what else could be wrong? Is it safe just to live with it like this? Also, the battery terminals have been cleaned.

Thanks for any and all help.

 

Make sure all the engine grounds are secure. A weak ground strap can cause this problem. It's also possible that a mechanic removed and forgot to reinstall during your work. I found this recently.

I would suggest getting a Battery Monitor ($15) from Walmart. It plugs into the cigarette lighter socket and provides continuous voltage indicator. Voltage w/ engine running should be about 13.7 volts when everything is working correctly. W/ full electric load, voltage should remain above 12.5 volts.

If voltage is running low, look for a slipping belt or perhaps damaged harmonic balance pulley assy. Inner/outer parts are slipping preventing alternator from turning over at correct speed. Check w/ high electrical load and 1500 rpm and you should be able to see if slippage is occurring.

good luck

 

Engine ground...

 

Could very well be a charging issue, only time I ever saw my batt light was when my alt was dying

 

Thats what I was thinking but he said he just replaced the alt.... So id have to say a grounding issue.

 

your alt. belt might be loose.

 

I wnet back to NTB and this week they are going to replace the alternator again to see what happens. I will update date later on with how it works out. Also, NTB mentioned that alternators seem to be a more common failure on the 1st generation CLs for whatever reason.

 

Ask them to check the harmonic balancer pulley for slippage. This can cause exactly your problem and is difficult to diagnose. Pulley may not slip on the inner rubber bushing at idle but begin to slip at speed or w/ load of lights, AC. Two alternators were installed on my son's TL before someone noticed the alternator was not turning as fast as it should be.

good luck

 

True that. Mine went at 65,000 miles. Almost left me sit on a highway around here, but I was able to nurse close to my house before it finally died.

 

Well, I had the alternator replaced for free under warranty, it turns out that the new one was faulty. This is now my 4th alternator replacement. Unbelievable.