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Question about 200 amp alternator.

  • Thread starter Thread starter The Green GT
  • Start date Start date May 10, 2006

The Green GT

No 13 year olds are safe around me.
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May 10, 2006
#1
  • May 10, 2006
  • #1
I just got my underdrive pulleys and I though my alternator might have been bad. now Im pretty sure it is. When I idle it goes almost to 8. now I have heard that you need to change some wires to run a 200 AMP alternator. Is this true and how hard are they to change?
 

propellerhead

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May 10, 2006
#2
  • May 10, 2006
  • #2
You might check with a few alternator vendors to confirm but a higher output alternator requires a higher RPM to "turn on". The turn on RPM is the RPM when it starts charging. Anything below that, it's just spinning. The factory one is something like 600 RPM, I think. Aftermarket ones are like 800 and up. Your underdrive pulleys are turning it slower so it may not be getting to the "turn on" RPM.
 

HISSIN50

"How long does it take to get help in here?
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#3
  • May 10, 2006
  • #3
Yep - more info about how you did your troubleshooting could help. Or let a parts store dynamically test the system (or take parts in for a bench test).

To run a new charge cable is cake. I ran mine in the same pathway as the OEM one. It goes from the alt to the distribution post on the side of the underhood fusebox. Piece of cake.

Good luck bud.
 

badstang123

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May 11, 2006
#4
  • May 11, 2006
  • #4
Propellerhead is right about needing the higher rpm's for output on a larger alternator. I ran into issues with this myself with my underdrive pulleys and 200 amp alternator. Some alternators may not have this problem, but many do. Why do you need a 200 amp output alternator? To address your question, if your going with a bigger alternator I would definately upgrade wires. It's a piece of cake to do. It probably wouldn't even take you an hour. Here is a link to what I did with mine (If you look at the other pages of my car you'll see why I upgraded to the 200 amp):

http://www.cardomain.com/ride/2327549/3
 

The Green GT

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#5
  • May 11, 2006
  • #5
Ok, thanks guys. As for why I think my alternator is bad, My friend who had the car before me said he though it was bad, and when I have the A/C on MAX, my car is very hard to start off from 1st gear. I figured that the alt wansnt pushing out enough amps. I got it tested but I dont trust them. They tpld my friend his alternator was fine and 1 day later it fried.
 

badstang123

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#6
  • May 11, 2006
  • #6
If you have doubts, pull the thing off (It will probably take you less than five minutes) and then take it down to the local autopart store. They can bench test it in no time (That might take another five minutes). Then you will know for sure.
 

HISSIN50

"How long does it take to get help in here?
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#7
  • May 11, 2006
  • #7
I would add that if an issue is intermittant, the regulator is a place to look. The bogging actually sounds like another issue from this side of the keyboard.

Good luck.
 

The Green GT

No 13 year olds are safe around me.
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#8
  • May 11, 2006
  • #8
HISSIN50 said:
I would add that if an issue is intermittant, the regulator is a place to look. The bogging actually sounds like another issue from this side of the keyboard.

Good luck.
Click to expand...
My buddy was expecting the ignition module to be the problem for a while too. But IDK
 

HISSIN50

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#9
  • May 11, 2006
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The load of the AC needs extra air compensation, which happens via the IAC [via the computer knowing the AC is on]. Without that input, the motor can bog pretty good till around 1500-2000 RPM (depending upon system charge).

My two cents.
 

The Green GT

No 13 year olds are safe around me.
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#10
  • May 11, 2006
  • #10
HISSIN50 said:
The load of the AC needs extra air compensation, which happens via the IAC [via the computer knowing the AC is on]. Without that input, the motor can bog pretty good till around 1500-2000 RPM (depending upon system charge).

My two cents.
Click to expand...
Well ,it dosent really bog once its moving, just to get it moving you have to give it more gas than normal and sort of ride the clutch or it will die.
 

HISSIN50

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#11
  • May 11, 2006
  • #11
Once you start moving, the throttle is open and the IAC is taken out of the equation (the issue improves).
 

The Green GT

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#12
  • May 11, 2006
  • #12
HISSIN50 said:
Once you start moving, the throttle is open and the IAC is taken out of the equation (the issue improves).
Click to expand...
Ok then, where is the IAC and how can I test it?
 

HISSIN50

"How long does it take to get help in here?
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#13
  • May 11, 2006
  • #13
The Green GT said:
Ok then, where is the IAC and how can I test it?
Click to expand...
This write-up might be of use.

It will take a couple mins to clean. As for testing, I only know the fox testing, which requires an oscilloscope to measure the square wave of the action. I think the 5N95 IAC works on a fixed displacement but I need to check.

I still would note that if the AC is overcharged, it will bog down hard (when you kick the AC on, the idle might drop a large bit).

Good luck.
 
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