It's just your oil pressure switch bro. Same thing happened to me on my last Titan (04) and I drove with it like that for about a year. It's actually a very easy fix. You'll get a bit dirty, but it's a pretty easy DIY project. The part isn't that expensive. I got mine from Autozone. Make sure you go ahead and buy a socket to fit the sensor if you don't already have one. It makes the job much easier. The sensor is located right next to the oil filter. All you do is unplug the old sensor, remove it, replace it with the new one, plug the new one in. Good luck man! I just crawled under my truck and did the switch while changing my oil. It's a pretty tight squeeze, but if I can do it, anyone can do it! LOL :bump: