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Rogmok
07-11-2003, 01:02 PM
so here's the problem, first I hear a loud, high pitch winding noise coming from my car.. i think its coming from the engine compartment.. but i'm not sure..

usually, as soon as i start hearing the high pitched winding noise.. my electrical system starts going crazy. Everytime i brake.. or even just let up off the gas, the entire electrical system will shut down (radio shuts off, needles drop to zero) but only for a split second.. and then everything comes back on. It happens so fast that i can't even notice unless i happen to be looking down at my gauges or radio...

It feels like there is not enough juice being pumped out to my car... i just changed the battery so its not that. Usually if i restart the car.. it goes away for a bit... but then comes back...

any idea of what the heck this is???!!!
537
07-14-2003, 09:45 AM
<!--QuoteBegin-Rogmok+Jul 11 2003, 11:02 AM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (Rogmok @ Jul 11 2003, 11:02 AM)</td></tr><tr><td id='QUOTE'><!--QuoteEBegin--> so here's the problem, first I hear a loud, high pitch winding noise coming from my car.. i think its coming from the engine compartment.. but i'm not sure..

usually, as soon as i start hearing the high pitched winding noise.. my electrical system starts going crazy. Everytime i brake.. or even just let up off the gas, the entire electrical system will shut down (radio shuts off, needles drop to zero) but only for a split second.. and then everything comes back on. It happens so fast that i can't even notice unless i happen to be looking down at my gauges or radio...

It feels like there is not enough juice being pumped out to my car... i just changed the battery so its not that. Usually if i restart the car.. it goes away for a bit... but then comes back...

any idea of what the heck this is???!!! [/b][/quote]
Might want to have your alternator looked at. The whine could be a dying shaft or a slipping serpentine belt. If you have access to a voltmeter, you might want to run a few tests to check voltage between the battery and the alternator.
mrazntre
07-19-2003, 01:57 AM
is the sound kinda like a screeching? do you see some smoke? do you smell burnt rubber?

sometimes the bearing in the alternator will SEIZE on you.. making a screeching noise as the belt tries to rotate the alternator pulley (which is SEIZED - which means it's locked in place and the bearing won't turn anymore). other times it can just be a loose alternator belt making a squeaking noise because it's not taut enough and slips on the pulley or tensioner pulley.


i think that autozone has an alternator testing machine..it'll hook right up while the alt is in your car. more effective though is if you pull the alternator out and try to spin the pulley by hand. you can tell if the pulley is seized because 1) it won't spin 2) it spins, but with a lot of resistance 3) the inside of the belt looks worn (as in, if the teeth on the belt are rounded off).

so basically it's 2 things:

1) Alternator is dying
2) Alternator belt is loose.
Rogmok
07-20-2003, 12:16 AM
nope.. not really a screeching noise, nor do i see any smoke..

its like a high whining noise, but it only happens occassionally.. which is why its hard to bring it to the shop cause usually it doesn't happen on days i bring it by.&nbsp;

I forget if mentioned this, but usually when i turn off myc ar and turn it back on, it stops.

if its the alternator, how come it only happens when i brake??&nbsp; (not that i don't trust you guys, just wondering though)
mrazntre
07-20-2003, 08:12 PM
what happens when you brake?

your throttlebody plate closes abruptly (as you lift your foot from the gas and onto the brake pedal), lowering your RPM's causing a dip in your RPM's. the motor must then equalize it's rpm's by opening up the throttle a bit (which then the MAF or MAP sensor senses how much air comes in and equates how much fuel should be sprayed). basically the alternator isn't spinning fast enough to provide proper voltage (it could be a worn brush).

an AC will lower your idle if your ECU doesn't compensate enough because you're allowing the compressor to come into play via belt (no longer free spinning pulley).

go get your free alternator check at autozone or similar franchise auto parts store.
537
07-21-2003, 02:21 PM
<!--QuoteBegin-mrazntre+Jul 20 2003, 06:12 PM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td>QUOTE (mrazntre @ Jul 20 2003, 06:12 PM)</td></tr><tr><td id='QUOTE'><!--QuoteEBegin--> what happens when you brake?

your throttlebody plate closes abruptly (as you lift your foot from the gas and onto the brake pedal), lowering your RPM's causing a dip in your RPM's. the motor must then equalize it's rpm's by opening up the throttle a bit (which then the MAF or MAP sensor senses how much air comes in and equates how much fuel should be sprayed). basically the alternator isn't spinning fast enough to provide proper voltage (it could be a worn brush).

an AC will lower your idle if your ECU doesn't compensate enough because you're allowing the compressor to come into play via belt (no longer free spinning pulley).

go get your free alternator check at autozone or similar franchise auto parts store. [/b][/quote]
Another reason why it would happen only when you brake is because as soon as you step on the pedal, you are putting additional load on the electrical system.&nbsp; Your alternator may be generating just enough current for your car during normal operation such as maintaining engine speed, powering your radio, dashboard instruments, and turn signals.&nbsp; However, as soon as you throw something else into the mix (your brake lights come on full power as you step on the pedal), all of a sudden your power requirements have just been increased, and your alternator is not capable of optimizing the flow of electricity.&nbsp;

This could be because of a slipping belt or a dying alternator.&nbsp;