One problem related to service engine light on has been reported for the 2007 Nissan Titan. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2007 Nissan Titan based on all problems reported for the 2007 Titan.
Started smelling gas fumes. Service engine light came on. Took the truck to advance auto to get the codes off of the computer and the tech said it has to do with the engine and that I should take it to the dealer. Dealer says it's the exhaust manifold and it has cracks in it. Would cost about $2000 for parts and labor.