Strange Electical problem

[Madcap]

So heres my problem. Last week I installed a full exhaust (down-pipe back). I finish up and open the door to get in and notice there are no interior lights. Then I find out my p/locks and windows aren't working. I check the fuses and they all looked ok. After about 1/2 hour of fuse checking and letting it run, all of a sudden it all comes back. BUT..... now my headlights noticeabley dim and the battery light comes on. I figure its the alternator and try to make from my folks house where I did the work to my Apt. in the city before it completely craps out. As I'm driving down the high I notice the Speedo seems of and the Tach is jumping around from 0 to 3000 like nuts. Needless to say I didn't make home. Tried to jump it, didnt work needed a tow.
OK, I thinking its GOTTA be the alternator. I swap it out for a new one and I jump start it still no power on the inside. Plus it doesnt hang on long and dies. So, I toss in a fresh battery and it starts and runs(but still no power inside). So, I now I gotta assume it would only be a matter of time until that battery dies if drive it like it is. Sorry for the long post but I need help badly.

 

[eviltalon1]

Did you check the fuses under the hood? I had the same problem and it was the 80 amp fuse under the hood.

 

[Morel]

Ground problem maybe?

 

[Madcap]

Did you check the fuses under the hood? I had the same problem and it was the 80 amp fuse under the hood.

I checked the fuses under the hood. Which one was it? I'll take another look and double check. And as far as I can tell the grounds seem ok.

 

[Madcap]

Well I checked under the hood again and low-and-behold I found a blown 100Amp fuse. Good news is I have all interior power function back again. BUT the battery still isnt holding a charge. Anyone ever run into a problem like this?????

 

[one_fast_tsi]

Have the alternator checked. Its possible to get a bad alternator. Happened to me 3 weeks ago. I bought one from advanced in a crunch ( boss yelled at me over that). It was bad. Took it back and got one from NAPA, all was well.