Ok my car has been driving me crazy. I have replaced my battery and alternator 3 days ago. Battery was free and alternator failed the test so I bought a new one. it's still giving me the same symptoms. It drove perfect for like 20mins but it happened again . First my anti-lock light comes on and the radio goes out. Then if I turn the lights on the AC lights flutter then shut off and the radio stays dead. Then a minute after the gauge cluster goes crazy and just basically flatlines and everything dies. Motor still running but it's not responsive to the gas pedal or anything because I'm guessing all the sensors and everything else is not responding. Basically has this happened to anyone before?? Car starts up fine but after it dies everything else like the lights and radio and AC work but it won't start again unless I put a battery charger on it. I need help trouble shooting because my wife just got a job and we have our schedule planned out with picking and dropping off our daughter at daycare.

I hope someone can help! I checked the smaller fuses but none are blown, I'll check the others but everything seems to be working..I'm seriously frustrated with this because it came out of nowhere.

My mods are UDP, RRM cold air intake and ported and polished intake manifold. That's it.

 

What's the weather been like where you are lately? Has it been raining alot?

 

Go test the alt.. If it test good replace the udp with the stock one and see how it runs with the stock pulley the alt could have been rebuilt poorly and it turning slower doesn't help? Also check the wires make sure they are tight and there's no corrosion causing resistance. Did you notice much gains from the PnP intake?

 

is the serpentine belt still there? lol

 

it's a bad alternator

 

Lol yeah the belt is still there Crans, it's crazy, maybe Ill take a video of what's happening of I can get it started later today after work.
No corrosion on the battery cables. They are tightened down. Alternator seriously seems fine, but I'm worried that something else could be killing the alternator if it ends up failing. Does our cars have voltage Regulators? Also no check engine light has come on at all.

The weather here in TX has been nice, except one or two days ago. Btw this first happened about 2 weeks ago and the car sat there for a week.
I am seriously stumped on this

 

Believe me its a brand new alternator, I changed it out Sunday and the battery was changed out Saturday. I'll pull it out and get it checked but I'm positive it's not the alternator.

 

the alternator is likely not charging the battery, so if it's new there's an open connection somewhere...

 

Voltage regulator should be built into the alt. When you do start it up try and get a multimeter on the battery and see if the alt is sending a charge to the battery if volts dont go up from 12.6 to 13-14 volts you have a open somewhere or the alt isn't charging.. Did you check the fusible link on the positive cable? Or alt. fuse?

 

no I didn't check the fusible link on the positive cable yet. Just to make sure how do I check it? Also I checked all fuses and they seemed fine, but which on is the alt. fuse again? I have wait until I'm home to check them but anything posted here, I'll be sure to check when I get off. Thanks.

 

I don't nec. think its a fuseable link, usually they are either bad or good, no in between. It definitely sounds like an alternator. It may be charging too high hence possible bad volt regulator, if there is too much voltage the car will shut many items off to so they don't get damaged. Is the new battery getting really hot by chance?

 

I haven't touched the battery like that but the overall engine bay has increased temps, but the temperature needle doesn't rise. Then again once everything starts going crazy and the gauge finally dies, my car basically keeps running but no electronics are on. Its as if its in limp mode. I know the throttle won't be responsive because all of the electronics dies and before it gets bad, I turn the car off.

Like in my first post, this started to happen about 2 weeks ago and the battery was dying slowly. I checked the alternator at the same time and it passed the test on the autozone machine. After I replaced the battery, it started doing everything I explained again. I took the alternator off brought it in Sunday & it failed that time. So thats when I replaced it with a new one and same crap keeps happening.

 

Yea your right donzilla if it was the one on the post the car wouldnt get power at all... The battery fuse is the bolted down one in the under the hood fuse box I believe it's yellow 60 amps 32v to test it you can get a test light and touch both sides and see if the light lights up on both sides.. Check voltage going to the battery if no voltage check fuse fuse looks fine hook up the alt. directly to the battery with jumper cables only one cable you dont need to hook it up to ground because its already grounded if the car smooths out its the wiring be very careful if you don't feel comfortable doing it don't try it I did it once on my sentra an it elimates defective parts and limits it to the connection.. If voltage is higher than 15v it's the alt.. Did you have the same guy test the alt.? Most those guys don't know the right end of a screwdriver unless they prove that they know what they're doing.. I've had bad experiences with them testing starters and battery's not sure how well they do with alts..

 

Well they hook the alternator up straight to a machine as if it was in a car. I'll bring the alternator into autozone and get it checked. I'll also get a test light to check the fuses. Yeah I don't feel comfortable with what your explaining to do haha.

 

Ok I had to jump start it and before the jump start the voltage on the battery was sitting at 9.5 varying and ten I jumped it, with the cables on it read 12.75-13 and when I removed the cables it dropped to 6 and varying up and down. So I'm thinking it's the alternator. I checked all of the fuses with a ligh test and they work. Am I really this unlucky with my original alternator going bad and then getting a bad one??