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Hi everybody. Since a few days, when I start my '90 Esprit SE from COLD, my battery/alternator light stays on for about a minute and a half, then it suddenly goes out. When I start driving immediatly, the light goes out a bit faster than when I just leave my car running alone. I don't have any starting problems, but it is most noticable when my headlights are on, because the moment the battery/alternator light goes out in my dash, my headlamps become much brighter!!! What can I check/fix? Thanks.
 

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Do you use a battery tender to keep the battery fully charged when you are not using the car? Is the tension on the belt for the alternator OK or is it loose? Is there any black goo dripping from the bottom of the alternator? You can take the car to most chain auto stores and they can check the battery and the alternator for free (at least you can in the US). If the battery is over 5 years old just replace it.
David Teitelbaum
 

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This is exactly like what happened with my '86 and it was due to a failing voltage regulator (aka "Black Goo") which is internal to the alternator. The brushes get goo on them and they stick and don't make proper contact with the armature until the goo gets warm and the brushes can move. The reason your light goes out faster when you drive right away is because the engine warms up faster. The problem will get progressively worse until it won't charge at all. In my case there was no sign of the goo until I actually took the alternator apart so the issue isn't always obvious. By all means double check that the battery is good but my money is on the alternator failing.
 

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I agree but whenever you have a problem with an alternator you should also be checking the battery and vice versa. Especially in an old car that may have an old battery. A bad charging system can leave a battery chronically low and that shortens a battery's life. A bad regulator can over-charge a battery and that also shortens a battery's life. One affects the other so you should be checking both. And all of the "big" electrical connections between them.
David Teitelbaum
 

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If you are going to replace the alternator consider using the Bosch 49ALX instead of the Valeo. More output and a more modern circuitry design. It requires a minor amount of adapting to install it in a 4 cylinder Esprit but most of those who have converted (me included) think it well worth the effort. There are a ton of posts on the topic so if you're interested research it here on the forum.
 
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