astra g 1.8 problem

[gaz2008]

right i got a 1.8 astra sri 1998 and i just fitted a amp and when the car is not running its fine but once you start it all you can here is loads of interference and you can here it going up the revs as you rev ive tried moving the earth no difference also tried running the live wire down the opposit side but still the same can some one help pls

[DaveCoupe]

Have you tried a larger contact earth, instead of moving it around?

[gaz2008]

no but the one i got is very thick.

[DaveCoupe]

I dont mean the thickness of the wire, i mean the actual surface contact it is making with the shell

[josh_mk3]

Can you hear the tone going up and down as you rev the car? it could be ground loop hum, you can buy reducers that go in line on your RCA's but there pritty whack . . .

Where your ground connects to the chassis make sure youv sanded the surrounding area down to bare metal on both sides and use some nice big washers.

OR your rca is picking up interference somewhere, what make is the cable? go buy a decent shielded cable and that might just solve your problem

[gaz2008]

i tried all of this and still nothing and yes you can he it rev in up and down cheers

[josh_mk3]

Im 90% sure its a ground problem, the noise your hearing is from your alternator, the next thing to do is to uprate the cables from the battery to ground, alternator to battery and make sure all the connections are good.

Unfortunately vauxhall electrics arnt the best . . .