Alternator whistle sound

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340Duster247 said:
Ok did another test. Alt at 1000rpm is putting out 14.1-2 volts. Checked at battery and is the same. The gauge on my tbinjection(fitech) reads 13.6-8.

Did ac check with no fans on and got the .1 at alt stud.
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That suggests voltage or FiTech is low due to drops, or FiTech measurement is not accurate. Well designed automotive ECUs, are powered from a relay, from direct dedicated battery feed, triggered from ignition circut. Is that how FiTech power circuit works? The readings indicate it is powered from ignition circuit. The original ignition circuit may not have the capacity to power FiTech, so load drops there may contribute to regulation issues.
 
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Just made one of these to clean up the alternat noise on my Dart. I've incuded a photo of the noise signal on my oscilloscope. I encased the whole thing in heat shrink. The side with the purple wire is the input, white to positive, purple to ground. The wire I used for the coil is 20 foot of 14 gauge house wiring. Make sure that you keep the windings tight and close together. Really cleaned up the AC ripple.
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KitCarlson said:
That suggests voltage or FiTech is low due to drops, or FiTech measurement is not accurate. Well designed automotive ECUs, are powered from a relay, from direct dedicated battery feed, triggered from ignition circut. Is that how FiTech power circuit works? The readings indicate it is powered from ignition circuit. The original ignition circuit may not have the capacity to power FiTech, so load drops there may contribute to regulation issues.
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Update: I ran a shorter run yesterday for the fitech and got it to read correctly. Now to figure out the whistle and light pulsing.
 
Alright guys now I'm just getting frustrated. Lol.
Took the car to a meet tonight. Weird the longer I drive the car the less voltage the alt puts out.
Come to a stop and 11.7 volts at idle......
That's the same as my garbage originally alt. It actually charges less then my original.
 
11.7V where? At FiTech? We have no idea where that is powered. Seems like posts from 67Dart273 and others suggest ways to test your system, have you done that?

Alternator needs to spin, it takes power, so a slipping belt will not generate much output.

The regulator needs a reliable voltage, it decides from that voltage, to energize the field or not. More field supplied, more output of alternator. But if the voltage that supplies the regulator cannot supply the necessary field current, due to very poor connections the alternator wimps out. Poor connections from bulkhead connectors, ignition switch IGN1, visible link.... Moderate connection problems, result in over voltage, but more severe problem, starves the field.

A relay can be used to bypass the problem, and 273Dart273 has a post on that in the forum.
 
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KitCarlson said:
11.7V where? At FiTech? We have no idea where that is powered. Seems like posts from 67Dart273 and others suggest ways to test your system, have you done that?

Alternator needs to spin, it takes power, so a slipping belt will not generate much output.

The regulator needs a reliable voltage, it decides from that voltage, to energize the field or not. More field supplied, more output of alternator. But if the voltage that supplies the regulator cannot supply the necessary field current, due to very poor connections the alternator wimps out. Poor connections from bulkhead connectors, ignition switch IGN1, visible link.... Moderate connection problems, result in over voltage, but more severe problem, starves the field.

A relay can be used to bypass the problem, and 273Dart273 has a post on that in the forum.
Click to expand...

Have you read my previous posts?
I've done their recommended tests and posted the results.
11.7 volts at fitech and at racepak. 12 volts at alt stud.
Bulkhead is bypassed ( alternator)
Belt is not slipping.
Will check over connections again tonight
 
Obviously alternator circuit is not working. It went from unstable to broke, it might be easier to find the problem now.
 
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