I just bought a 2002 S10 4x4 4.3 with 44,000 miles. Runs great but I get loud engine / electrical noise over the standard radio and my XM radio. Any ideas how I can correct the problem ?

 

factory xm or aftermarket?

 

plug and play XM unit powered thru power port

 

Any kind of aftermarket amplifier?

 

Does the noise come through the speakers when using FM radio as well as XM? or just the XM?
If it is just the XM, you could be picking up a lot of noise when using the accessory outlet.
If it is through fm stations as well as when your using the xm, your problem could be a por radio ground, or a poor ground in the antenna circuit...usualy occurs at the antenna base where it attaches to the body

 

have same problem with a 2000 blazer aftermarket and original radio have tried ground to dash havent tried antenna yet