Idling issue after installing Stereo?????

[02RedSoul]

Hey guys I just installed a Kenwood X890(sexy deck) to replace my factory cd player and now all of sudden i'm have issues with my RPM. After I finished the install and turned on the car it actually died the first two times. The 3rd time is stayed on but it began idling real low cause heavy vibration and almost seeming like it was going to cut out again. I'm tried to go back to the factory player but now get the same results. Secondly I'm made sure there are no loose connections as they all have been soldered and taped. What could be causing this issue because I'm kind of scared to drive my car?

[NeFaRiOuS_SLE]

Did you get some massive subwoofers or performed any engine upgrades? It shouldn't interfere with anything unless you didn't disconnect the battery and shorted something out during the installation.