I just picked up a '99 250 V!0 SD w/ 33k. The first week of driving everything was ok but over the last few days it's developed a very loud (I can hear it while driving) "click/pop" from the pass side exhaust manifold (not a heat shield). I guessing a loose bolt(s) attaching the manifold to the head.

Has anyone had or heard of this before; does anyone have the torque specs for the manifold bolts; and what tech manuals are people using?

Thanks in advance: GARY

 

You said that you could hear it while driving. How can you tell for sure that it's the manifold popping?

I have not heard of this before.

 

The noise (I think it's the same one) continues after the engine is shut off. It is very distinct when heard from the pass side wheel well. I tried putting a screwdriver against the manifold and head to listen and to see if I can feel anything when the noise occurs but I am unable to pinpoint it. The kicker is that the rate at which it occurs and repeats is random, and it doesn't seem to have anything to do w/ anything else, i.e. AC on or off, in or out of FWD, gear selection, etc. Unless someone can point me in a direction I'm thinking about loosening all the manifold nuts and then retorquing to see if it'll go away.

 

The torque on those nuts is 18 ftlbs.......just be careful.......they studs break easily. You have low miles so you sould be ok if you decide to do it.

 

My 99 V-10, 55K miles, does the same thing. And you are right, totally random.

I generally only get it when the truck is turned off after running it. But last month it started doing it while driving. Pretty loud pop -- sounds like thin metal being struck by metal (not to say that is happening, just the sound). Recently, tho, I haven't noticed it. Either I am used to it or it stopped.

I just assumed it was the manifold or heat shield flexing as the temp changed.

Curious if you had any updated on this?