What is the drive cycle for a 2003 Nissan Sentra SE?

Did you recently clear the trouble codes or disconnect the battery? Once all codes are cleared, the computer will not display systems 'ready' until they go through an evaluation cycle. Some of the systems require a certain number of drive cycles before they will display 'ready'. A drive cycle is usually starting the engine from a cold start (based on coolant temperature) and driving until certain conditions are met. I don't know what the requirements are for your car, but my 2003 pickup truck requires more than 10 drive cycles before it will make the O2 sensors and evaporative emissions 'ready'. Most states only require that a certain number of systems are showing 'ready' to pass emissions certification.

What is not ready?

One of the 8 Emission Monitors?

Drive cycles have to be looked up in factory manuals
& done by a repair shop, NOT the vehicle owner

Seldom do you need to do a drive cycle

If a drive cycle is done for a reason, there is no driving a vehicle
hundreds of miles, as you hear about

I would guess you have an Emissions Failure

Exhaust Converter
Oxygen Sensors
Cylinder Misfires
Egr Issue
Evap System

What ever codes you have, will tell you the system to component test

Need scan tool to look at data,thus a repair shop

theres always one on the intake manifold working its way down to catalytic convertor is the oxygen sensor 1 heater circuit(pre cat conv) signal while terminal #25 is oxygen sensor 2 heater circuit (post cat conv)

lOOK BEHIND THE GLOVE COMPARTMENT. Compartmet is probabily plastic and all you have to do is push in real hard to get them past dash board.

They should have been able to do it in the shop. Some of the sensors will reset everytime you turn off the car so that may well be whats happening. Try another emission place and see what they say but do not tell them you were "just at another place"

Under the hood, there is a fuse block. I believe it is on the driver's side of your vehicle. Open that box, and pull the "ECU" fuse. Leave the fuse out for at least 5 minutes. Put the fuse back in, start the car, and let it idle for at least another 5 minutes. Do not drive the car, touch the gas, or even look at the gas pedal for these 5 minutes, as the ECU is remapping itself. This will properly reset the ecu and clear the codes. After this you may drive the car.

sounds like a computer module problem . have the computer diagnostic scan done at your nissan dealer. good luck mister bill

I have the same car and I know there was a TSB for the ECM . I know the ECM issue has cause some cars to stall while driving

One of the common things that gets missed at times is the radiator is down in cooling antifreeze. The car will act as normal during the warm up cycle and then the temperature guage will rise and then it will slowly come back down as the thermostat opens and/or the electric cooling fans come on. In actuality the engine is overheating, but it is not boiling over. The level of abtifreeze is at just the right level of lowness that you experience this phenomenon. After the engine cools off , (DO NOT REMOVE WHEN HOT - YOU CAN GET SCALDED WITH BOILING WATER/ANTIFREEZE)), remove the radiator cap and check the level within the radiator and also the antifreeze reservoir level. You can buy a 50-50 mix of antifreeze and water that is ready to put into the radiator. If the level in both the radiator and reservoir are correct, you may have a bad thermostat or some other problem.
Bob - 2003 Nissan Sentra SE-R SPEC V