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headlights/interior lights flicker, voltage drops, weird issue...

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Old Apr 19, 2010 | 09:27 AM
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Default headlights/interior lights flicker, voltage drops, weird issue...

recently my lights both inside and outside seem to flicker almost all the time. by outside i mean headlights. when i rev the car at idle they flicker more intensely. also when i drive and say i go over a speed bump and have to put my clutch in quickly. when i do that, the voltometer drops from a healthy 13 down to 8-9 almost in the red. then it goes back up.

also my passenger window will barely close. it goes pretty good until about 4 inches from closing, then creeps the rest of the way. if the power in the cabin is on but the car off, the window will stop before closing and i have to start the car to get more juice to get it to close completely. the window motor is brand new, and in fact, i just changed it recently because the motor before this one was doing the same thing and i thought it was bad, but clearly not. i don't know if this is related to the flickering lights; the driver's side window is speedy.

my first thought was battery, it checked out healthy. i also checked the alternator and it was fine. any ideas? i am so confused! is there a short somewhere? thanks. just fyi, i have a powerful sound system and a stock alternator...it's been playing loud for 4 years and the alternator has withstood the power, but even though it checks out okay in an autozone test, i'm wondering if there is really a problem with it after all.
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Old Apr 19, 2010 | 10:35 AM
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I'm having some similar problems...
but in addition, my car drops to the 8-9 region for longer periods of time now than when the problem first started. My alternator didn't test bad with the autozone test until yesterday. The car stopped reading the healthy 'over 13' mark at all...

When I get it switched out, I'll let you know if it was, indeed, the problem causing the voltage drop like that.
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Old Apr 19, 2010 | 10:40 AM
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you had the light dimming issue as well?

is it a pretty logical assumption to say it's the alternator? i kind of think that's what it is, and if it isn't, probably a very weird electrical short that could be nearly impossible to pinpoint.
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Old Apr 19, 2010 | 11:07 AM
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my car does the same thing. when my car starts up, especially at night, the lights were flicker slightly but my voltage and everything is fine. Car has done this from the first day I got it. It's a little more noticeable now with my cam but car has never given my any problems. I am also just running the crappy factory system. I have replaced the battery and did the same thing.

My theory is....if it aint broke yet why bother with it.
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Old Apr 19, 2010 | 11:14 AM
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Originally Posted by sscamaroburn02
my car does the same thing. when my car starts up, especially at night, the lights were flicker slightly but my voltage and everything is fine. Car has done this from the first day I got it. It's a little more noticeable now with my cam but car has never given my any problems. I am also just running the crappy factory system. I have replaced the battery and did the same thing.

My theory is....if it aint broke yet why bother with it.
that has been my theory, but it has gotten worse as of late, and the voltometer is showing signs of dropping. also i don't want to really be in the middle of the country on the highway when my alternator dies.
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Old Apr 19, 2010 | 11:52 AM
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i read some people with similar problems upgraded the engine to chassis wire. which wire is that? when people say upgrade the big 3, i have already done 2 of those, just not the engine to chassis. any help on where it is (pics?) and how big of a replacement wire you should use to upgrade would be helpful. the other two i used 2 gauge, so they should be good.
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Old Apr 19, 2010 | 12:03 PM
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my car will do it when I push in my clutch comming to a stop, voltage will drop to 9-10 then back to 13... Not all the time tho only ocasionally and more noticable at night.
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Old Apr 19, 2010 | 12:42 PM
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Yeah... when my voltage drops, my car starts missing also... so it's kind of a pretty huge problem for me, especially now that the voltage is ALWAYS right at the red zone.
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Old Apr 19, 2010 | 01:07 PM
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Originally Posted by tuffluck
i read some people with similar problems upgraded the engine to chassis wire. which wire is that? when people say upgrade the big 3, i have already done 2 of those, just not the engine to chassis. any help on where it is (pics?) and how big of a replacement wire you should use to upgrade would be helpful. the other two i used 2 gauge, so they should be good.
I just used the alternator bracket for the engine to ground. Connected one end to the alternator bracket and the other to the shock strut bolt on the passengers side.Wrapped the cable in split loom to protect it. I checked the resistance with a volt meter and it was a very good grounding point after removing the paint underneath the bolt itself.Since you used 2ga for the other wires,that should be ok.I know some people that have used 1ga wire for the big 3.I wasn't worried about using a ground on the engine block,since the voltage will find the least amount of resistance to travel anyways.
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Old Apr 19, 2010 | 01:17 PM
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so where is the original engine to chassis ground? that's what i'm trying to figure out.
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Old Apr 19, 2010 | 01:26 PM
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Originally Posted by tuffluck
so where is the original engine to chassis ground? that's what i'm trying to figure out.
I really didn't go looking,but I did fine one on the drivers side.It was underneath the air intake duct and was attached to the front of the block and ran to the frame by a thin grounding wire.I had to remove the duct to get to it.If I recall correctly,it was right near my ignition coil.Anyways,the bolt was big,but the wire was small and attached with a small bolt. I was just going to use the bolt on the engine and drill another hole for a bigger grounding area on the frame.

update: buddy told me he had one by the starter and one by the idler.
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Old Apr 19, 2010 | 02:39 PM
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i guess i don't entirely understand what the engine to chassis ground is...you can just run any grounding cable from the enging to the chassis, you don't have to replace the exact other one. what do most people use for the ground? i just want the easiest thing. i believe my alternator is going out, but hopefully a 30 minute try on this project can tell me for sure.
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Old Apr 19, 2010 | 02:41 PM
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So... would solid motor mounts count as a 'new grounding wire'?
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Old Apr 19, 2010 | 03:10 PM
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Originally Posted by tuffluck
i guess i don't entirely understand what the engine to chassis ground is...you can just run any grounding cable from the enging to the chassis, you don't have to replace the exact other one. what do most people use for the ground? i just want the easiest thing. i believe my alternator is going out, but hopefully a 30 minute try on this project can tell me for sure.
You don't have to worry about the other engine ground,you can leave it.Voltage will always find the least amount of resistance to travel,therefore the bigger wire will be the path the voltage will take.That's why I used the alternator bracket,it was easy and just attached it to the shock tower bolt.
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Old Apr 19, 2010 | 07:37 PM
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does anyone have pictures of this? man, i just spent a gruesome 2 hours trying to get off a bolt from the alternator that i swear is impossible. it's just below the first front spark plug on the driver's side, under the header. there is a heat shield there and as much as i tried with several pivoting sockets, i couldn't get the damn thing. i think i did more harm than good with the damn thing. i finally got it tightened back enough i think.

which alternator bolt are you using??? on the front? they are so close to the pulleys? i don't know what to do, i gave up. i couldn't see any viable bolts to use. i need some help--does anyone have any tips for this piece of the big 3??? ls1??
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Old Apr 19, 2010 | 07:44 PM
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Originally Posted by tuffluck
does anyone have pictures of this? man, i just spent a gruesome 2 hours trying to get off a bolt from the alternator that i swear is impossible. it's just below the first front spark plug on the driver's side, under the header. there is a heat shield there and as much as i tried with several pivoting sockets, i couldn't get the damn thing. i think i did more harm than good with the damn thing. i finally got it tightened back enough i think.

which alternator bolt are you using??? on the front? they are so close to the pulleys? i don't know what to do, i gave up. i couldn't see any viable bolts to use. i need some help--does anyone have any tips for this piece of the big 3??? ls1??
Just swapped my alternator. Took less than an hour.

The ground they're probably talking about is the bolt on the back of the alternator. Should have a rubber boot over it... and should have a ground wire already attached to it.

All of my problems went away except my surging/missing... so I guess that's due to some other problem. But the alternator fixed everything else.
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Old Apr 19, 2010 | 08:32 PM
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My 97 only has a positive connection on it,so I used the mounting bolt that holds the alternator in place. Now if your alternator has a pos and neg,then YES,just attach the new wire to it and find a good ground.The shock mount bolt was easier for me to connect to the body.
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Old Apr 19, 2010 | 08:46 PM
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Originally Posted by AxisOfOil
Just swapped my alternator. Took less than an hour.

The ground they're probably talking about is the bolt on the back of the alternator. Should have a rubber boot over it... and should have a ground wire already attached to it.

All of my problems went away except my surging/missing... so I guess that's due to some other problem. But the alternator fixed everything else.
which bolts (and how many) did you have to undo to get the alternator off? when i said the one facing the driver's seat underneath the driver's side header, did you have to take that one off? i could not get that one loosened for the life of me. any help you can give would be great. thanks.
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Old Apr 19, 2010 | 10:00 PM
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Originally Posted by tuffluck
which bolts (and how many) did you have to undo to get the alternator off? when i said the one facing the driver's seat underneath the driver's side header, did you have to take that one off? i could not get that one loosened for the life of me. any help you can give would be great. thanks.
Yeah. There's that one, it's like a 10mm I think. Has to come off.
Then two long bolts through the alternator from the front, 13mm.
It's helpful to remove the other 13mm bolt and remove the bracket the alternator is mounted to at the same time.

Of course... take the serpentine belt off and disconnect the battery and the electrical cables first.

If you're replacing the alternator, look at the places where there are holes or threaded holes on the new one. lol.
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Old Apr 20, 2010 | 09:17 AM
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Originally Posted by AxisOfOil
Yeah. There's that one, it's like a 10mm I think. Has to come off.
Then two long bolts through the alternator from the front, 13mm.
It's helpful to remove the other 13mm bolt and remove the bracket the alternator is mounted to at the same time.

Of course... take the serpentine belt off and disconnect the battery and the electrical cables first.

If you're replacing the alternator, look at the places where there are holes or threaded holes on the new one. lol.
the one i am talking about is 13mm. how did you get it? i mean i had a swivel, a 4" extension, and a 12" extension and i couldn't turn it at all.
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