My 03 Altima 2.5 L is smoking and has loss of power just after exiting off the interstate.Could the timing chain have jumped time to cause this problem?It was running fine before I let off the gas pedal to exit off the interstate then when I went to take off again the motor had no power and was blowing out blue smoke everywhere.

The blue smoke is an indication of oil being burned. So yes the timing might have skipped. How many miles are on the car? The timing belt should be replaced every so many miles, 70k-120k depending on the car, it will be in the manual.

So I think that yes, the timing is probably the problem as the blue smoke is usually the biggest indicator of oil being burned and the timing belt being thrown off a tooth, will cause both the loss of power and the oil being burned. I would buy a Chilton or Haynes manual if you intend to fix the timing yourself as it will have directions and a diagram that you will need on hand. good luck and let me know if you need anything else

Benjamin

Sounds more like you have blown the head gasket.
If it is the timing chain you will hear rattling noise . If it is the head gasket, water will go very soon and engine will probably not re-start.

In both situations is a major fault you will need to take the car to a garage to fix the problem.