Hey guys.

Ok this is my problem, my head unit which is a clarion has been working well for over 3 years now on my big setup , but yesterday i noticed that the head would shut of once i put the volume up (no speakers are running of it , only thro the amps) . it then got to a point where the deck would only turn on or have power when the car was NOT on.. the second i turn the car on the deck would not work at all. so i pulled the dash part of just then to have alook and it all seemed fine , i also took the main plug at the back of the deck off to have a closer look to see if any connections where dodgy , but it was all good, i pluged it back in and started my car , and my cars idle was all f**k up? turned the car off , took the main plug back out , started the car and the car runs smooth... if i plug it in again the cars idle is all f**k up , and cuts out when you give gas.

WHAT the hell does having the deck connected have anything to do with how the engine idles?

What could cause this type of thing?

Any help would be great!

sounds to me that the unit is pluged into wires behind the dash which it shouldnt be
there is a plug just for the head unit,make sure all the wires are pluged into it.