I'm really struggling with locating the source of a tapping that my 98 is having. Usually with my stethoscope I can pinpoint the location of the noise and narrow down the cause, but this one I can't find anything!

In order of thought and checked:
Lifter- probed valley pan and nothing
Exhaust leak- slight smell but nothing I can find
Head Gasket- not losing coolant, no milky oil
Liner- same as HG and also taps cold and warm

I've started probing the transmission even but still nothing. The only thing I can tell is that it's near the back of the motor and seems slightly more predominant on the passenger side.

It all started after an oil change because I stupidly topped off the oil with WAY too much (In a rush and just threw oil in without checking dip before leaving). Ran it for 30 miles overfilled before noticed and corrected.


P.S. I did my pre-post searches, but comparing noises to other peoples descriptions is like comparing a dog turd to cat turd (same **** slightly different)

 

Bump, hoping this sounds familiar to someone

 

Have you checked the spark plugs, wires, coils? A head gasket leak does sound like that if it's away from coolant ports, can be any cylinder too. Putting a hand near will feel the exhaust pulses. It jets super hot so be careful. As far as overfilling it, could be a coincidence. The reason not to overfill is due to the crank. Like hitting a solid surface and can twist it.

 

It doesn't sound mechanical to me. Exhaust gasket leak (you say you checked this) or non-water jacket head gasket leak.

 

Damn that engine is clean!

 

I made sure the wires were still seated properly on both ends, I have not pulled plugs though. Hardest part with sensing exhaust leak was feeling the air movement from the fan. I'll pull the fan and check for hot air in the morning. Thank you.

I pray for exhaust leak between the two. I'll check for leaks more in the morning. Thanks!

Thank you! I try to keep good care of all the vehicles I drive.

 

I forgot to mention that while driving, the noise is almost non existent while coasting (foot off gas) but comes right back during acceleration and idle. If that helps any

 

The number 8 spark plug can be treacherous to tighten. The exhaust manifold can get in the way and you can wind up partially cross threading the plug. The 'tick' could be an exhaust leak which would also explain the exhaust gas in the engine bay.

I did not have noticeable exhaust gas in the engine bay, but here is what mine sounded like.


http://vid796.photobucket.com/albums...xhaustleak.mp4

IMO yours sounds a bit more 'metallic' but it is very difficult to differentiate.

 

Walt, the video wouldn't load for me. Gave me the cat picture with "Photos not found".

Started tinkering in the truck this morning. Started with pulling plugs and inspecting. All looked good other than wetness on the threads of plug 6 (possibly too much antiseize). Double checked the tightness of the exhaust manifold bolts and snugged them all up. I fired it up, started checking for air pressure and instantly felt it around cylinder 8.

Upon further inspection the exhaust gasket had broken and started pushing out.

Autozone wants $40 for a full set of $20 gaskets.... wtf?
But I am curious as to what people are using for exhaust gaskets? Between the single port thicker gasket and double port multi layer gasket, which do you prefer?

I had the multi layer before and they looked absolutely terrible when I pulled them off 7 months after install (layers broken, charred black, bent, etc.) so I switched to the fatter single.

 

hope this works....
http://vid796.photobucket.com/albums...xhaustleak.mp4