It usually will not throw a code. A cracked manifold will make a clicking or tapping sound that changes frequency with engine RPM, and is most noticed when driving near a building or wall. Many times the sound will lessen as the engine heats up.
The problem is if you get too nitpicky with searching for suspicious sounds, you might think you have an exhaust leak when in fact it may be just the injectors or perhaps a clogged Evap control valve.
What I'd like to really know is how the stealership techs are checking the exhaust manifolds to verify if they have cracks in them. I tried looking myself, but the heatshields seem to cover everything up. However, I don't think the techs are removing the heatsheilds when they check for manifold cracks. They must be doing something else.
Well, yesterday when I was driving and I gunned it from around 20mph to 40ishmph I heard a ticking/clicking noise on the passenger side of the truck. So when I pulled it in to the garage I revved the engine to around 3.5 rpm and heard nothing.
Was it still cold when you romped on it? If not, it may not be a manifold leak. If the crack is big enough, it'll open and close depending on engine temperature and load.
Mine doesn't tick/click like that, so you definitely have something that's not right. I'd just bring it in and pay the diagnostic fee to have them look at it That way, you'll know for sure if it's the infamous cracked manifold/s or not.
It wasn't cold, I had drove it for about and hour then it sat for around thirty minutes, then drove again for 15 min before I got on it a little when I heard the noise. It may not be anything, the noise isn't that loud. It may be the muffler since the muffler that I have on it is a used Magnaflow.(around 40,000 miles on it)
A forum community dedicated to Nissan Titan owners and enthusiasts including the 4x4 and XD. Come join the discussion about performance, modifications, classifieds, troubleshooting, maintenance, and more!