I installed an amp yesterdayin my c3 and I can hear engine noise. Prior to installing the amp I never heard any engine noise so I believe the problem is with the amp not the stereo.Here are some facts. What should I do?

1. I ran a 8 gauge to battery(behind drivers seat)
2. I ran a ground from the rear wall through the floor to the rear sway bar mount. Approx 2.5 feet.
3. I bought Monster cable RCA's and ran them fromthe head unit to the amp on the oppostie side of the car(opposite from the ground and power. :cry

 

Check the ground with a multi meter. If you don't have a multi meter, buy one at wal-mart for $9. You want to have the needle move the same amount as when you hook the multi meter to the battery itself.

It sounds like you installed it correctly with the power down one side and the signal down the other.

A low quality amp can introduce noise into the system even if it is installed correctly. Is this amp running a sub or components?

Is your ignition system modified anyway (high performance wires/coil, etc?)



[Modified by leolufse, 5:23 PM 3/17/2003]

 

:iagree: If you've checked the ground and still have a problem you can try running the ground back to the batt and see if that changes anything...

Also does your vette still have the stock ignition shielding?

 

The amp is a US Acoustics
It is running two infinity 6.5 in the kick panels-mids
the ignition system is stock

 

I do not have the iginitio shielding however, w/o the amp there is no interfearence so this should not matter. I will try to ground directly to the battery :crazy: after going crazy to do it to the chassis now I am going back to the battery im going :crazy:

 

Keep us posted if that solves the problem.

 

Its the ground..

Check motor ground
Starter ground
Battery ground

High output motors seem to be the worst at this noise making..EQs on some amps make noise also. Dont run power wires down the same side as the rca or speaker wire..Makes noise too.

Rob :thumbs:

 

UPDATE, I grounded directly to the battery and the interfearence got WORSE! Funny thing is I can only hear it on High pass and full range, when I switch to low pass the noise completly goes away. What should I check next? :confused:

 

notice the post's saying " ground "...???.....remember ,the juice in your car
( dc )..travels from NEG to POS,,.not POS to neg,,,,thats why the ground is so important...all grounds,motor to chssy,,amp to chssy..bat to chssy..amp case to ground...etc...after that it is " white noise " getting into wires acting as an antenna to your amp..and the amp amplifies it..usually easy fixes..
noises that go up and down with motor rpm are by alterator.

 

Ok So I will check all the grounds from battery to frame, motor, chassie ect. I thought it ment to check the ground to the amp. The noise increases with the RPM's so it must be from the alternator, if the "ground" does not fix the problem do I need a new alternator or is there a sound supression device I can attach to it. The alt is only 3 years old.-Thanks for all the help so far! TK :cheers:

 

Another guy in a C3 had the same problem, he disovered an unused wire harness near the distributor, maybe this will help:

http://forums.corvetteforum.com/zerothread?id=521055

 

I'm having the same problem. I had a 42 amp alternator and used a noise suppressor and had no noise at all. Now I upgraded my alt to a 100 amp and can't get rid of the noise. The noise goes up and down with the rpm's. I will be following this topic closely.

 

ok,,,,,new alts installed,,new amps installed,,new problems....
one of the most frustrating problems in my ( two way ) radio repair stint has been noise on recieve..
basicaly two areas to look at,,,power feed and antenna..
if you unplug the ant and noise stops,,well thats one scenario,,if it stays then power feed lines are next,,,after that there are a few other things to look at..
computers are one,,,in tank fuel pumps another,,,tachs can make noise..
old wireing..etc..
what you are hearing is called " white noise "...
the whining noise as rpm's go up and down is usually from alt....a " poping " noise is from plugs or plug wires..resistor plugs and wires have to be used.
also amps without good filtering and that are not truly "linear" will make noise worse..
any filters, ( caps ) should be as close to unit (radio,amp ) as posible.
filters ( caps ) for alts can be used also..
ground is is most important....quality shielded audio wires also best.
toroid chokes can also be used in extreme case..on ant or supply wires..
the ARRL website for ham radio operators has some good stuff on noise supresion from radio techs with many years of working on that prob..
if you have tried everything feel free to email me....if i can get my brain to work , one prob at a time is easier..

 

TJKirby - try this. Take a scrap piece of wire lying around and strip both ends. Connect one end to the chassis of the reciever and one to a ground somewhere. See if grounding the reciever helps. I experienced this problem in the past where I checked EVERYTHING from the ground of the amps to the connection of the speakers etc etc... and found that the reciever's chassis itself need to be grounded. I know it sounds strange but it helped me out in 3 different cases. You don't necessary have to dismantle the whole reciever, just pull it out a bit and put one of the wire to the sleeve of the reciever and the other end to a door jamb or something that is metal and is grounded like the bolts to the seats. It'll take u 5 mins to figure it out if that is the case. IF it is, then just attach a wire inside the dash to the reciever's chassis and to a ground. Let us know what happens. :cheers: