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Whats Causing this loud annoying noise? by mitchjl22
Started on: 12-17-2013 01:49 AM
Replies: 6 (272 views)
Last post by: mitchjl22 on 12-17-2013 08:34 PM
mitchjl22
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Report this Post12-17-2013 01:49 AM Click Here to See the Profile for mitchjl22Send a Private Message to mitchjl22Edit/Delete MessageReply w/QuoteDirect Link to This Post


What could be causing this loud belt noise?

[This message has been edited by mitchjl22 (edited 12-17-2013).]

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mitchjl22
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Report this Post12-17-2013 01:51 AM Click Here to See the Profile for mitchjl22Send a Private Message to mitchjl22Edit/Delete MessageReply w/QuoteDirect Link to This Post
I just watched again, it looks like my alternator isn't working....look at the gauge and the brightness of the lights.... whats going on there?
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mitchjl22
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Report this Post12-17-2013 02:12 AM Click Here to See the Profile for mitchjl22Send a Private Message to mitchjl22Edit/Delete MessageReply w/QuoteDirect Link to This Post

mitchjl22

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87" GT 2004 3800sc from GTP.

Isn't the alternator clutched, does something have to be programmed into the PCM for that? Was it possibly left out?

//www.fiero.nl/forum/Forum2/HTML/122658.html

 
quote
Originally posted by XgovernmentAgent:

I believe the older PCMs cannot activate the S3 alternator because it needs a 5v PWM signal from the pcm. AFAIK the PCMs we can use for the SCII/III swaps are not capable of creating the correct signal to activate the alternator. Many headaches were involved in this discovery. A one wire alternator or a SC2 alternator will be going in place.


What does this mean for me?

[This message has been edited by mitchjl22 (edited 12-17-2013).]

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hercimer01
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Report this Post12-17-2013 02:26 AM Click Here to See the Profile for hercimer01Send a Private Message to hercimer01Edit/Delete MessageReply w/QuoteDirect Link to This Post
You're right, the alternator isn't working. What one did you use?

I had a weird noise under hard acceleration. Mine was caused from the boost hose to the fuel pressure regulator being loose causing fuel starvation.

------------------
Project Genisis Lo Budget 3800SC swap

88 Coupe under construction

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Report this Post12-17-2013 08:54 AM Click Here to See the Profile for FIEROFLYERSend a Private Message to FIEROFLYEREdit/Delete MessageReply w/QuoteDirect Link to This Post
Is the alt lined up properly belt wise and the belt the proper tension. I have used the newer style alternators before with the older PCMs with no problems charging. Also if it was a compatibility problem you should not have the noise just a no charge situation. I would also suspect the bearing in the alt is bad that is if the noise is the alt for sure which can be hard to tell for sure when the belt also turns other components plus tensioner and idler pulleys any of which can cause noise. Dan
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mitchjl22
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Report this Post12-17-2013 12:31 PM Click Here to See the Profile for mitchjl22Send a Private Message to mitchjl22Edit/Delete MessageReply w/QuoteDirect Link to This Post
hercimer01: I'm using the stock SIII alt, it was a great lower mileage one before the swap, now its not working.

FIEROFLYER: The reason i was wondering if it was a compatibility issue, is because from what I understand its a clutched alternator. If the clutch wasn't engaged (however it works) it might not be charging and causing this noise. I just simply don't know

It may have gotten unplugged, i'll check it again when I get to school this afternoon
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mitchjl22
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Report this Post12-17-2013 08:34 PM Click Here to See the Profile for mitchjl22Send a Private Message to mitchjl22Edit/Delete MessageReply w/QuoteDirect Link to This Post

mitchjl22

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Okay, everything is wired up and works, the problem is, the tensioner. The belt simply isn't tight enough. I got my tensioner at a junkyard for $11 and it came off of the supercharger side of another 3800. It has the square nub on the back that is supposed to prevent it from rotating, but the tensioner is rotated too loose, if i were to add some more material under the nub, it would effectively tighten the belt (So I believe). I'll try to get this squared away tomorrow, but so far everything is A+.
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