Silverado electrical issues


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OK, so my '03 Silverado is on the brink of nickel and diming me I think.

For the past month or so I've noticed the headlights dimming when at idle. The AC will "surge" when I'm at a light, then yesterday as I got in the truck to go home I turned it over and it died. So I tried again and it made a clicking sound and wouldn't turn over. So I tried again and it turned over, but ran rough for a bit.

Any ideas?

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Sounds like an alternator to me. Would start with checking for loose cables though, check battery and ground to the frame. If everything is tight then get the battery and alternator checked out. Alternators for those trucks are not too terribly bad and that would be the worst case scenario I would think. Last one I replaced was either the one on my truck or the one on the yukon. I replaced it with a genuine delco part which was considerably higher than the auto zone part and it was around $165 if I remember right.

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I think William is dead on. Personally I would take the alternator (if it turns out to be the problem) to a repair shop. A new set of brushes is way cheaper than a new or rebuilt alternator, and you'll have a much better quality unit. I used to work for Delco/Worldwide Auto which is most likely what you'll get at any parts house and personally feel they are crap.

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It could be the alternator, but I don't understand why you tried to start it twice and it just clicked, then it started. Almost sounds like a bad battery post. On the side posts the positive will sometimes leak a bit of acid around the post, then the post literally rots out of the battery. pull on the cables at the battery. Could just be a loose battery connector too.

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I'll check the battery. Thinking about it now, that battery is probably 3 or 4 years old.

I know it's due for plugs and wires, but with my pole barn fees looming, I can't afford it right now.

Thanks guys.

Plugs and wires should not be too bad Chris, if it needs them.

I would really check your connections close before replacing anything. Just the week before last I had a dragging starter and turned out when I checked everything that my positive side battery cable had loosened up just enough that the battery was not charging like it should have. Tightened it up put the battery on the charger and everything is fine now.

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Battery cable checked out. Not corroded, not loose. Probably alternator I'm thinking. I've noticed the voltage gauge fluctuating a bit while the truck is running. When the alternator went on my S10 a few years back, the voltage indicator was doing wild swings from 9 volts up to like 14.

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Battery cable checked out. Not corroded, not loose. Probably alternator I'm thinking. I've noticed the voltage gauge fluctuating a bit while the truck is running. When the alternator went on my S10 a few years back, the voltage indicator was doing wild swings from 9 volts up to like 14.

Some fluctuation is probably ok with different engine speeds so long as it stays above normal charging voltage at an idle. Would be sure to also check the connections at the alternator Chris. Should be a nut for the positive cable, there was on the 98 and older models anyway. Will also have a harness with 3 or 4 wires in it that plugs in.

Pulling the alternator is pretty simple, most part stores can test it for you.

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She's going to the shop today. It's been running fine last day or two. Mechanic seemed to be a little bamboozled. Asked if the voltage light was coming on, and it hasn't. I told him the gauge was fluctuating a bit here and there.

Rather be safe than sorry. My S10 stranded me the one day and it cost me a tow, so I don't want that to happen again.

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