One problem related to engine has been reported for the 2004 Nissan Titan. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2004 Nissan Titan based on all problems reported for the 2004 Titan.
I was driving a 2004 Nissan Titan approximately 35 mph. The motor cut off and I coasted to a stop. The motor restarted after a few minutes and I attempted to get to a repair shop. After driving approx 3 miles, the motor cut off again. I was able to restart the engine after a few minutes and drove approx 1 mile to a repair shop. After leaving the repair shop, I called two Nissan dealers and both said that it sounded like a recall that Nissan had planned for early Dec 2010. One of them suggested that I have the repair shop run a diagnostic to see if anything showed as a problem. If nothing showed then it was probably related to the scheduled recall. I contacted the repair shop and relayed the info. After running the diagnostic, I was told that there were no warnings. I have major concerns about driving a vehicle with an engine that will just cut off for no apparent reason. When I asked the two dealers what could be done, I was told not much since the recall isn't due to go into effect until Dec and that they (the dealers) had been instructed to not do anything until Dec. It appears that Nissan is aware of the problem but chooses to ignore the potential consequences.