I got my alt installed Friday and when it was first hooked up, I got a 14.2 reading. My mechanic drove it home about 5 blocks while I trailed and it was still fine.
I got in maybe 10 minutes later to give it the test. I popped the face on my radio which displays the voltage and it was still 14.2. I took off around the corner and gave the car a little gas and around 40 mph the voltage suddenly dropped to 12.7 and slowly dipping lower. Battery light popped on too.
Yesterday was rainy so I didn't mess with it. Today I tried a few things none of which worked. I put my DMM on the alt and it reads 12.3 (same as batteries)
I'm not sure what else I can try. My trusty stock alt was giving me a 13.5-13.9 reading when it was taken off. I swapped it because I am running 3k+ watts and may do more.
Does this sound like a bad alternator? All of my connections are tight, the belt is not slipping and it did work for all of like 15 minutes.
Car is a 2000 Chrysler 300M. I'm not sure if there is a fuse or something that I can check. I just don't want to go through the trouble of having it taken off and put back on if something else can be tried first.
