Well after a LONG detailing session with my radio on the whole time I ended up draining my battery. So I jump start it and it seems fine for a day or 2. When I started today it almost died on me then RPM's picked up to normal. However when I have it gas it would only go up about another 200 rpms. So I take my battery out thinking I killed it brought it to AutoZone and they told me yes... the battery is dead. I bought a new battery and started up just fine after I installed it. A few hours later I went to park my car and now it's doing the same thing. Started it and it almost died then RPM's back up to normal and when I give it gas it wont rev up.

Does this sound like an alternator problem?

 

not sure what the symptoms of a bad alternator are but an easy way to check if the alt is charging the battery is to get a voltmeter and measure the voltage at the battery terminals. it should be over 13V.

oh yeah, i'm not sure if your original battery was bad in the first place since you have the symptoms with a new battery.

 

Well, I had to pull my car into nissan. They kept it a couple days and found that there was a code in the computer that said the Electronic Throttle Control Actuator (the black square looking thing on the back of the throttle body) was bad. They replaced it and the throttle gasket for a grand total of $738. Thank God I have an extended warranty. So I only had to pay a $50 deductable.

 

To test your alternator, you will need a volt meter. Connect your volt meter to your battery and start your car. It should read 14-ish volts. Turn your lights, radio, flashers, and high beams on and verify that your volt stays around 14. If you see the volts slowly dropping, then most likely your alternator is faulty.

 

I had this problem with my Z. First I thought was the battery, then sparkplugs, then MAF, then CAM/Crank sensor, then spark plug coil but later died completly. Here are som posible ALTERNATOR symptoms:
-Check volt meter needle (dashboard) if fluctuate between 12v and 14v all the time various times
-Dash light should not FLICKER
-(With Volt meter DCvolt black to black and red to red on battery) When engine runing and all lights, radio, AC...Volt meter number start dropping means Alternator it is NOT charging correctly
-Volt meter on dashboard should NOT either go up to higher than 15v (Alt over charging)
-When car runing, RPM should be steady but if it goes up and down quickly, Alt problem
-If you smell burn plastic or wire could be a FAN but also an Alternator
-If car after runing normal randomly died and there is no power at all (Alt problem)
*Price for an ALTERNATOR at a dealer ±$300-400 at AutoZone, O'reilly ...etc $133-160 with core charge (Not New) they give you life warranty. Ask first before purchase. Labor for installation $45-100 hr (in Texas)
*If I am wrong please correct me so I can get better and help others. Thank you and God bless