hearing engine through radio

[phatcap]

whenever i listen to AM radio and the truck is running, i can hear static pops that increase and decrease with the rpms. when the truck is off its clear as a bell. it seems like i've heard something about this before, something to do with the plug wires? what causes this and is it a problem or something i should be worried about fixing?

btw, it doesn't do it when the radio is on FM and they're ngk wires.

 

[fastpakr]

When's the last time you replaced your plugs and wires?

 

[feellnfroggy]

Its an aftermarket radio isnt it? There is a filter that goes on the (positive/ground?) wire of the stereo the reduces the interference from the plugs and alternator. Factorys tereos have them but aftermarkets dont always have them. I would go talk to a stereo shop about it, they will prolly point it out right away, Just dont fall for any of the "you needa 300 dollar capacitor to fix this" lines.

 

[phatcap]

its the stock radio and i changed my plugs and wires back in june '08, only about 15,000 miles ago.

 

[Shran]

Some plug wires come with RF shielding, perhaps your new ones did not.

 

[Wicked_Sludge]

AM radio? whats that?

check your stereos ground. im willing to bet the connection isnt solid. add a few more if you'd like, just to be sure.

 

[MAKG]

It CAN be due to arcing ignition secondaries (spark plugs, wires, or coil/coil pack) outside the engine.

Though you should also hear it in FM between stations with the volume cranked.

 

[phatcap]

haha, yeah. i was wondering when someone would chime in with the "wtf, you listen to AM?" comment. only if there's a detroit pistons game on and i'm not at home to watch, i'll listen to it instead. thanks for the suggestions though. i'll check the ground and do some research on those plug wires.

it doesn't signify a problem though right? like the wires arcing or something...idk. another thing i just remembered, it didn't do this before i replaced the stock antenna with a shorty one. wonder if that has something to do with it...hmmm.