2000 Nissan Sentra stalls at stop-and-go traffic

My car stalls at stop-and-go traffic. When I come to complete stop, and move maybe 10ft with sudden acceleration, and come to complete stop with hard break, the car stalls. I have check engine light. The code said that I need to change O2 sensors. All FOUR of them. So I purchase original manufactured parts, and replaced all of them. Reset the error code, drove for 70 miles or so, and the same error code again. AND the car still stalls. What’s going on?

[b] I have check engine light. The code said that I need to change O2 sensors. All FOUR of them.[/b]

No it does not say that.  What it does say is there is something wrong with the converter system.  It may or may not involve the converter(s).  

How about getting the real codes (they will look like [P1234].  That will help a lot.  Has you car received all the recommended maintenance?  In other words, how old are the spark plugs and wires?  When was the last time you replaced the air and fuel filters?  

How long have you had this stalling problem?  Why did you bring your car to the dealer?      Dealers are no better (or worse) than independent mechanics for almost anything you might need done on your car.  They will almost always charge more per hour and often more for parts and supplies.  They also tend to look at repairs a little different than the independent. 

A dealer may well recommend work that strictly may not be needed, but could be connected to the problem or maybe replace a part when a little repair would fix it ALMOST as good a new.  

There is no need to bring your car to the dealer for any service other than service that is going to be paid for by a recall or original warrantee.  During the warranty period be sure to have all required (as listed in the owner's manual) maintenance done and to document all maintenance work.

I suggest that most people would be better off finding a good independent (Not working for a chain) mechanic. 

Note: Never ever use a quick oil change place. They are fast cheap and very very bad.

Thanks for the reply.

Unfortunately, I don’t remember all the codes (four codes were showing). I think one of them was P1710, which was car running too lean. I had to change all four oxygen sensors because the codes said that I needed bank 1 and bank 2 sensors changed. Plus, the previous O2 sensors were damaged.

The catalytic converter was changed by the dealer, under warranty, about 2 years ago. So it is relatively new.

The air filters were changed/cleaned whenever I do oil change. When I asked to change the fuel filters, the mechanic said that there is no fuel filters for Sentra.

The stalling was going on for 4 months or so. It is been happening more frequently within last 2 weeks.

So, again, what is wrong with my car? Is it ECM?

I took my vehicle in to the dealer. The dealer re-flash the ECM, and used known good ECM to check if the stalling problem goes away. The answer was NO. So, it was determined that ECM was not the cause of stalling. The dealer finally came to a conclusion, after two days of diagnosis, that MAF (Mass Air Flow) sensor was faulty. So I changed the MAF, and the car was running fine. No stalling. However, after about 120 miles into driving, the check engine light came up. No stalling, yet, the just check engine light. I am going to take the car back to the dealer. I will post the updates later on.

I doubt if this CEL has anything to do with your stalling problems. They likely are connected to the pollution control stuff. Get the actual codes (like P1234) and post them here. Maybe we can give you some help on those.