you probably have a dead cylinder, most likely from a bad spark plug wire, but there are many other possible causes ranging from a fouled plug to a burned valve.etc
OR...a plugged/dead fuel injector..SIMPLE to test (could try several rounds of techron in your gas)
Testing and changing a bad fuel injector is very simple. Just unplug the plastic wire connection while the engine is running (push the plastic clip in on the back to release the lock), no change in the way the engine runs indicates that your injector is bad, a good injector will cause the engine to run worse when the electrical connection is un-plugged. Simply remove the 2 screws and the cover, spray a little lubricant around the base while you turn the unit (cresent wrench works great) to loosen/break the o-ring seal, then gently but forcibly pry/pull the old injector straight out. Spray a little lubrication (wd-40 works fine) on the new o-rings and and push/seat the new unit in place, replace the cap and screws and re-connect the electrical before starting. Can be purchased cheap on e-bay!
Testing With a Multimeter/Ohmreader
1 Set your multimeter to check for resistance or turn on the ohmmeter.
2 Disconnect the wires to the injector.
3 Place your meter's leads on each of the two injector terminals. Read the meter display.
4 Check your service manual for your car's resistance number. Most fuel injectors have a resistance of between 10 to 18 ohms.
5 Test each injector. If any of the injector readings are higher or lower than they should be, you need to replace them.
Listening
1 Put a long screwdriver directly on the injector while the car is running.
2 Hold the handle up to your ear. You should be able to hear a rhythmic clicking sound. If you do, your injector is good. Hearing a clunk-clunk type noise means you have found your problem.
3 Hearing silence or unusual clicking patterns means either the injector, wires or plunger may be bad or sticking. You will either have to clean or replace them.
One of the reasons for a 2003 Nissan Sentra to run rough and stall out when it comes to stop is a bad oxygen sensor. Another cause for the running rough could also be a dirty air cleaner.
I have an 05 sentra that shifts rough from 1rst to 2nd, especially when cold. You find any answers? thanks, Brian brewnut@hotmail.com
check dist. cap for water
Vacuum leak, bad spark plugs, plug wires, or all three. Replace all vacuum hoses, plugs and plug wires. Replace the hoses one at a time so as to not get confused.
Check your spark plugs and fuel filter.
the check engine light is blinking and my 03 Nissan exterra is running rough
why does my vr commodore idle rough when at complete stop
On the 1.6 litre Sentra engines you should not have to change a timing chain until well over 250,000 miles if ever. This engine has an automatic chain tensioner that keeps the chain tight so that it will not jump teeth when stretched due to wear. I have heard of early 90s engines developing gear tooth cupping that prevents the engine from retaining proper ignition timing. This causes the engine to run a little rough. I have never SEEN this though.
The year, make, model and engine info would help but in general it could be a vacuum leak or time for a tune up.
if the car is running rough or if plugs are in poor condition
vacuum leak
A lot depends on when it is sputtering. Is it hesitating under acceleration? That is what happens most commonly in eclipses. It is probably a misfire in one of the cylinders. Change your plugs and wires.