I have a 4.6 liter that chirps under load when the engine is warm. I've checked belt, pulleys and bearings, not it. The sound seems to be coming from the back and top of engine. I can put the trans in drive, turn on the AC and cause it to chirp when the compressor kicks in (puts engine under load). It stops when the compressor kicks out (no load). I almost suspect some kind of vacuum leak. I also see other post saying possible exhause leak, but it does not sound like exhaust which to me sounds more like clicks than chirp. Any help would be greatly appreciated.
If its OK I also have this problem with the radio resetting every time I start the engine. I cleaned the battery posts but did not help. Any ideas on this too?