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Discussion Starter #1
This morning I got in my car after letting it run for a while to warm up, I noticed a battery light on and the DIC beeping and showing the Alternator light? I was like um? Then I gave her a little bit of gas and boom gone? I don't know if it was caused by being to cold or what? but man I am ready for summer again over here lol! Any ideas on why this happened? Thanks.
 

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Your alternator is getting lazy. It triggers by RPMs, and now at idle the magnetic field that it generates is appearing to be growing weaker with the age of the part. You should look at having it tested. It may just be borderline.

What is your battery charge level? Does it fluctuate?

The charging circuit appears to have an issue, but you won't know how bad until you test it.

It might help to check your battery connections as well as the alternator power connections to be sure nothing is loose.
 

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Best guess - the alternator output was too low because touching the throttle nudged up the rpms and the lights went off. Why? Maybe the alternator doesn't like winters too (lol).
 

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Discussion Starter #4
Your alternator is getting lazy. It triggers by RPMs, and now at idle the magnetic field that it generates is appearing to be growing weaker with the age of the part. You should look at having it tested. It may just be borderline.

What is your battery charge level? Does it fluctuate?

The charging circuit appears to have an issue, but you won't know how bad until you test it.

It might help to check your battery connections as well as the alternator power connections to be sure nothing is loose.
the battery normally stays charged at 65%- 83%. And the alternator looks pretty new, charging cables connected to the battery are brand new along with the battery so I don't know if it was triggered by the cold or what? I currently don't know the voltage but I can get that later on my lunch break, it went away so I don't know? Also before the tire fault light came on as well but went away ? And never came back. Idk thanks for the help ill let ya know the % and levels.
 

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Discussion Starter #5
the battery normally stays charged at 65%- 83%. And the alternator looks pretty new, charging cables connected to the battery are brand new along with the battery so I don't know if it was triggered by the cold or what? I currently don't know the voltage but I can get that later on my lunch break, it went away so I don't know? Also before the tire fault light came on as well but went away ? And never came back. Idk thanks for the help ill let ya know the % and levels.
Also the rpms are low idles at 494-545 in park when warm, when its a cold start it stays at 1000rpm then goes down after it warms up, I normally never drive it until its warmed up and goes down so I don't damage anything.
 

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Another possibility is a stretched serpentine belt. Do a visual inspection of the belt checking for looseness by pulling upwards on it with the engine off, key off out the ignition. Or, with the engine running, stand back and watch for slack or play as it passes over the various pulleys.
 

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I wish I could remember what mine idled at before the tune, but it was mostly over 600RPMs. For yours to idle at even less than 500 that seems a bit low and may be indicative of another problem. That seems like a sluggish idle to me.

Your alternator circuit may not like those low RPMs. Check it's operating RPM range to see if that is low.
 

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Discussion Starter #9
I wish I could remember what mine idled at before the tune, but it was mostly over 600RPMs. For yours to idle at even less than 500 that seems a bit low and may be indicative of another problem. That seems like a sluggish idle to me.

Your alternator circuit may not like those low RPMs. Check it's operating RPM range to see if that is low.
just checked again and it idles at 568 the lowest, but coming to a stop in drive around 600rpm so its normal, battery was at 67.4% charge and circuit was 14.4v i think lol
 

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Well, keep monitoring it. A simple irregular start shouldn't cut on the warning light. That said the problem is probably relatively minor in nature given that your idle RPMs seem fine.

Seems your belt as suggested before may be the culprit, and it may just be the cold hardening the rubber causing it to slip at first.
 

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Discussion Starter #11
Well, keep monitoring it. A simple irregular start shouldn't cut on the warning light. That said the problem is probably relatively minor in nature given that your idle RPMs seem fine.

Seems your belt as suggested before may be the culprit, and it may just be the cold hardening the rubber causing it to slip at first.
Very well could be, didn't think of that. It seems fixed we looked at it yesterday when I had it on the lift we did a full undercoat with black rubber after scrapping off some rust, and replaced the O2 sensor, Ever sense we replaced it and I reset the computer the car feels much more responsive no more delays in pushing the pedal and no more waiting to accelerate in passing gear lol xD. Thanks for the help! :grin2:
 
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