One problem related to anti-theft controller has been reported for the 2003 Nissan Altima. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2003 Nissan Altima based on all problems reported for the 2003 Altima.
Car will not start at times, car will start and not idle past 1500 rpm's or drive over 5 miles an hour. Service engine soon light stays on. First I was told the anti theft in the cars computer system was causing the problem, next I was told the computer did not re-learn the setup. Next I was told it is a throttle position sensor. Tired of the same problem being blamed on different things and then re-occurring. This problem do to the speed of the car can cause serious hazards by not having the power to maintain the speed limits !.