Okay, I did a search and couldn't find a thread that answered my questions...so even though I'm sure someone else has had the same issue, I'm asking again. Sorry for that. I've got an '07 GT with 35K miles. CAI, Pypes, SCT programer with custom tune. Recently it started throwing error code P0340, Camshaft positioning Sensor. I replaced both sensors. Still got the code. I heard that particular code is often a precursor to the alternator going bad, so I bought and installed a 130 Amp "performance" Alternator from American Muscle ( PA Performance Mustang Alternator - 130 Amp (05-09 GT) at AmericanMuscle.com - Free Shipping! ). I cleared the DTC...but immediatly it started throwing the same code again. And now it's also throwing error code P03444 and the battery light is on. Wierd thing is, when I start the car, the batter light isn't on. After it warms up a bit, it comes on. But if I get it up over 2K RPM's, the batter light goes off. As the car gets warmer, I have to run higher and higher RPM's to make it turn off. I'm about to go sell the damn thing and buy a Fox body if it keeps pissing me off. Any suggestions?