first problem-, eveery time i try and start the car the battery is dead, and its a brand new battery

Second- with battery charged, try and start car and it just cranks no firing, after priming it a few times it barely starts and then runs fine.

Third- after running for like 20 min, the car starts to hesitate bad, and shake when i press the gas pedal

the car is throwing a bank 2 sensor 2 o2 malfunction code,

can this code cause all these problems, and if so why the starting issues, possibly opti again?

 

well the battery shouldn't just be dead everytime you start the car.. unless its a defective battery with a bad cell or somthing... or unless your alternator isn't charging it anymore after you've been driving..

 

I had this issue. The battery was taking on to much load and was discharging. You seem to have 2 problems. One, I would check your ground connections on your battery. So your throwing an 02 code, those sympotoms could be o2's going bad, what you think guys? How many miles on the car?

 

Just a thought--

Sounds like it could be the alternator. I don't know how long the car would run on just battery power, but the 20 minute problem & MAF code might be caused by your battery is dying because it is supplying all the power instead of the alternator.

 

unplug both o2s and crank the car it should be in open loop. if the car stays running, undo the batery and if the car keeps running the alternator is good.

 

also you can unplug the maf. all it will do is through a code and revert back to speed density

i would try unpluging the maf first.

 

Lordi lord...

1) If your alternator went bad you can just tell by checking the voltage gage in you dashboard when your car starts. It should go up higher than when the car is off... The battery supplys 12 volts but the alternator is good for 13.8. you should see a voltage increase.


2) if your chargin system/alternator went bad then you wont see a voltage increase when the car fires up but instead will see slow voltage drop in your voltage meter inside your dash. if in doubt buy one "el cheapo" multi tester from radio shack and read the voltage right at your battery.

3) New batteries are not perfect. I had one with a slow leak. everytime they tested it came up just fine. However if the car sat for 3 days... the battery would die again. Hard to convice the Auto Part Store morons this could happen. I had to purchase a brand new one again from the same store then I asked the store manager to charge and hold my first new batt for three days and I would come back to have the voltage checked... sure enough it was defective. Thats how I got my money back.

4) There is such thing as bad battery conections. Your battery may be just fine but if there is rust between the conector and your battery then it wont start and it even seems as if your battery is dead... check em out. A little sand paper goes a long way here.


5) If your Voltage drops with the engine on there is a point where the PCM maybe unable to continue with normal operations. I think its the ignition the first one to die when the voltage drops drastically, its one or the other. Have your battery/chargin system/battery conection problems fixed first then you diagnose any sensors or other parts problems if they still exist. My O2 sensors have a heating element. without enough voltage I am sure they may misbehave..but then maybe not. see what I mean?


Marvin