engine noise heard from radio
#1
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Thread Starter
engine noise heard from radio
Something weird is going on with my car. When i turn on the radio, i hear this whisteling noise that i think is coming from the speakers. As i accelerate the car the noise grows, if i turn on the blinkers, the whistling noise will go along with the timing of the blinkers and then if i power off the radio i no longer hear any whisteling noise at all. Needless to say its pretty annoying. Does anyone have any idea of what it could be. By the way, i do have an aftermarket radio.
thanks!!
thanks!!
#4
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Thread Starter
well somthing else that happens is that every once in a while my light kinda dim as if there was a loss in power. It happens frequently...like ill just be sitting at a light and my lights will dim and the whistling noise will die down a bit then continue. I though there may be a short but how the heck am i suppose to figure it out???
#5
Instructor
noise
I had a spark plug wire that was bad and the spark was arcing with my headers and causing a noise in my speakers. Hopefully its a simple fix like this...
Bobby
Bobby
#6
Le Mans Master
Is it a stock radio? If not, then could be a ground loop problem (bad ground).
If the radio is stock, then it could be the alternator is starting to go out. One of the diodes is probably dead.
When sitting at a light, the cooling fan probably comes on and takes some load (dimming lights for a sec.) and changes the sound you are hearing.
If the radio is stock, then it could be the alternator is starting to go out. One of the diodes is probably dead.
When sitting at a light, the cooling fan probably comes on and takes some load (dimming lights for a sec.) and changes the sound you are hearing.
#8
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CI 6,7,8,9,11 Vet
St. Jude Donor '08
Sounds like the filtering capability of your alternator is suspect. Your getting AC ripple in your DC circuit. There are also capacitors in the alternator that could be bad. If you have a bad alternator, take your car to a certified Alternator repair shop and have them check the alternator. If it is BAD, have them repair your alternator.
Try this:
Get a digital volt meter and measure the output of the alternator using the AC Voltage scale. You can read the output of the alternator from the large terminal on the back of the alternator. You should see ZERO AC volts. Make sure that you scale the meter down to a low voltage scale cause the AC voltage only needs to minute to cause problems like you see. You should see about 14 Volts DC.
Do you hear the noise with the engine off???
BC
Try this:
Get a digital volt meter and measure the output of the alternator using the AC Voltage scale. You can read the output of the alternator from the large terminal on the back of the alternator. You should see ZERO AC volts. Make sure that you scale the meter down to a low voltage scale cause the AC voltage only needs to minute to cause problems like you see. You should see about 14 Volts DC.
Do you hear the noise with the engine off???
BC
#9
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This is a tough one to diagnose, no doubt about it. I put in an aftermarket radio, amp, speakers, capacitor, the works. Had the same problem. After testing all the grounding, swapping the alternator, installing noise filters of various types in various locations, here's what I found was the problem for me. When putting in the Kenwood deck and the 1/2 din EQ, it's all longer than the stock deck so you have to bend over the stock bracket in the dash. I figured out that the RCA connectors at the back of my EQ were touching the metal frame that holds the radio. A few adjustments (bends to the old bracket with some pliers) and some electrical tape around the RCA's for contact shielding, and the noise was completely gone.
A pretty simple fix I should have checked first when I noticed the 'snug' fit of aftermarket deck. Good luck on your system.
A pretty simple fix I should have checked first when I noticed the 'snug' fit of aftermarket deck. Good luck on your system.