hey guys went to drive my truck the other day and fired it up and walked back into the house to let it warm up. As I walked by the exhaust I heard a loud ticking or missing coming through the pipe. No crazy smoke other than the normal slight haze at idle when cold cmpletely clears after it up to temp. Smooth all the way through the rpms pulls hard still and I had someone hold the truck at about 12 to 1500 rpms and I don't hear it only at idle. I don't get it. Any clue? Any advice is appreciated thanks.

 

A miss is definately noticeable and you'll know it if you have it. Maybe a tick without a miss? Have you ever adjusted or had the valve lash adjusted on your rockers? Could also be an injector getting goofy on you. Try ideling the engine with the hood up, and see if the ticking is coming from somewhere under the valve cover. Im not sure if your injector lines are held in place with brackets to keep them from vibrating. If so, touch each injector line and feel for the pulse that is in time with the offending tick. Might just be a vibrating injector line thats not held tightly. Also a sticky lifter comes to mind.

 

well I bought the truck from a friend and he kept on top of the maintenance I know that. He was a cummins mechanic. And yes fuel lines are held in place with brackets and all are tight. I drove the truck more and it's not a miss it runs was to smooth and pulsto good to be a miss. I was leaning towards an injector also. Whatsscrewing with me tho is that I hear in at the tailpipe not so much underthe hood.

 

im actually having this same issue, truck runs great but on idle its just a little off from smooth and i hear a quiet little tick

 

when my doughnut gasket started to get tired on the turbo it made a defined tick if you listened hard enough, it sure didnt sound like an exhaust leak but it was.

 

ya it's weird. I was thinking an injector but it runs to smooth and to clean in my opinion. But idk was also thinking an injector because the truck has a little haze of smoke when it's cold. But it clears up when the truck is warmed up and ( I took the fuel plate out and put the stock one back in to see about smoke and it burns clean as could be when at operating temp). And the truck made the same sound with no exhaust on it. I had to move it when it had so exhaust was right off the turbo. Could it be a cracked eshaust manifold or a blown out gasket? But I don't really hear it as much under the hood.

 

without hearing it I cant really tell you? if its a bad gasket and you cant hear it with the hood up maybe its on the bottom side of the manifold. if its a stock manifold check it for cracks. has boost fell off a little bit? you wont notice a huge difference in spool up on a bad manifold gasket but prolly some. also i get a LARGE plume of white smoke on start up when temps are around freezing and below. clears up almost instantly.

 

12v supply and return lines are know to "tap"?

 

no I haven't noticed any boost issues but I haven't towed with it either. Today just empty I stomped it in 2nd and shifted into 3rd and hit 32psi which is about normal for my truck. Ya the manifold doesn't seem to have any cracks in it unless it's on the bottom side where I can't see it. If it was a cracked manifold or blown out gasket wouldn't I hear that under the hood instead of at the tailpipe? And yes mystery I know about the fuel line "tap" but it's not at the fuel tank. I can hear the "tap" plain as day between the cab and bed that's just normal I know that sound. The noise is coming through the exhaust.