While driving down the road or even at idel, all of a suden my lights on my dash and stereo start to die and the rpm's drop below 500 and the engine dies. Then it takes a few seconds to start the engine and I have to stay about 1500 RPM before I can put it back in drive otherwise it will die again.

So I checked the battery and the alternator and the alternator passed the test at the store, but the battery failed. I bought a new battery and within 15 minutes the same thing happened. I scanned the trouble code and got code 53 (System Voltage High) I also got code 46 (vehicle antitheft system failure) I started the car this morning and it took 10 minutes of warming it up before it would idle on its own. Then I tested the battery with a volt meter and got 12.5 engine off and 14.1 at idle. (13.8 with lights, radio and A/C on) I have checked the connections and everything looks good.

I have had this same issue for months now and can't get it resolved. I need all the help I can get!! In the past I've also got trouble codes 44 (Bank 1 (left) Oxygen Sensor (O2S) Circuit (lean exhaust indicated) and a code about my AC charging system connections. And I failed California Smog Emmissions test!!! WHAT THE H*** IS GOING ON?????!!!!!!????!!!!
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First, go to an auto electric place to have them do a check on your system----can't be too sure with just having the alternator checked by a "store". As far as not passing emissions, whenever your battery goes dead and your pcm dies, you need to drive around for at least 20-30 miles to get your pcm back up to where the emissions people can get good readings. Or if you are throwing codes at the emissions place you need to ask them which codes---or essentially what the problem is. Every now and again, I get a code for one of my 02s---the car only has 10 grand on it, so it may or may not be a bad 02---they don't last forever, but you never know.

My guess is that if I was to go through emisssions while the damn thing was thowing an 02 code, they probably wouldn't pass me either. You can have someone, who is willing, reset your 02 code so at least temporarily it may not show "check engine lite" while you go through emissions.

If your battery and connections are good, including terminals, and engine cable connections, then perhaps your alt is boogered, or at least someting with the charging system.

My first inclination is to believe that your charging system is boogered and killing your pcm which needs to be reset by driving around as I mentioned. So get the charging system checked first so that you at least can begin to go through the process of elimination, step by step until the problem is resolved. JMHO

 

I'll go check the charging system as you suggested. But as far as the O2 Sensors go, those were replaced just prior to the smog test, and all codes were cleared. They can't give me a reason for the fail because it was a Check Only Station. No repairs allowed.

 

It doesn't matter if they allow fixing at the station or not, they must tell you, in writing what didn't pass---and if it was because they couldn't get a reading, it might be because your pcm was not fully recovered from the dead battery.

Think about it---if it doesn't pass, how can you get it fixed if you don't know why it failed----I don't mean that they should tell you exactly what your problem is, only why it didn't pass------emissions, lack of readout, etc.

I have, on occasion, left one station, when it didn't pass, and drive to another and have it checked again, just to make sure that they weren't being chicken $hit or the testing equipment wasn't boogered. JMHO

 

I misunderstood what you were saying. They gave me a printout of the readings for the emmissions test. I was triple the legal limit. All 3 emmissions catagories failed. But they couldnt tell me why it was failing so bad.

 

which happens first diming lights or the low rpm. if the low rpm happens first then you might not have a charging system malfunction at all. the dimming lights could just be due to the low rpm. if your emissions were three times the legal limit in all categoris that would be really strange unless you have no catalitic converter, which you say in your sig was recently replaced. can you be more specific with your emission readings. gas analisis can sometimes point to the posible cause of a driveablility issue.

 

When you go to start it back up does the engine spin at the normal speed or does it sound like its dragging?

14.1v while the engine is running is enough to maintain a fully charged battery. 12.4v is what a battery should have with the vehicle off. Your charging system sounds find i wouldnt worry about that, it sounds like you need to head more into the drivability area, it sounds like you have a problem somewhere with the pcm or maybe a short somewhere , i would start with getting it scanned at an actual "shop" with a good scanner and not a simple code reader it will drastically reduce your diagnostic time. good luck

 

sounds like a bad coolant temp sensor, or maybe an o2 sensor

 

It pretty much starts with the RPM's going down. I happened again today and I tested with a volt meter while it was acting up. With the RPM's in the 2500-3000 range (I needed that to keep the engine running) I got 13.6 volts. That was with No load at all, just the engine. I had tested it 10 minutes prior to that and I got a 14.5 volts at no load.

As far as the specific readings on the smog, I can't find the paperwork because it was over 6 months ago that I did that. But the gas, my miles per gallon went from 20 to 11mpg

why a coolant sensor? (O2 sensors are new)