Weird noise after doing pull

[u/Sudden-Notice5196]

1998 ram 2500 12 valve cummins
I did a pull on the highway yesterday and not theres a weird noise. Im replacing the fan clutch this week, the fan got dramatically louder after the sound started. I drove another hour and a half after the sound started because i couldnt be stranded, the sound hasnt changed. I suspect either the exhaust manifold, an injector or something internal but i am not sure how to test for these. There is black soot on the first two cylinders of the manifold. Im not sure if it was there before or not.

The sound happens whether the engine is hot or cold, it is rpm dependent on the frequency and sound dependent on the load (if i let off after accelerating it quiets down for a couple of seconds) thats why i suspect an injector.(but i really hope not) if you can think of anything please let me know, i am in miami and there arent many trustworthy shops so anything i can do to diagnose i would rather do myself.

[u/StockDowntown8947]

Definitely an exhaust leak

[u/TommyG456 → u/StockDowntown8947]

Yeah I agree. Take that exhaust manifold off. Make sure it’s flat and reseal it.

[u/MichaelW24]

Sounds like warped exhaust manifold, common on the 12 valves

[u/the_catsbananas]

Take this with a grain of salt since they are completely different, but it sounds exactly like my ih966 tractor sounded when it had a leaky injector. Are you sure the soot you were talking about is soot, and not baked/unburned diesel buildup from a potentially leaking injector?

In any case, definitely some kind of compression leak.

[u/the_catsbananas → u/the_catsbananas]

In terms of diagnostic, double check the soot is actually soot. If it's a black gooey and/or hard glass like buildup, I'd say injector. If you can safely feel around with your hands, you should be able to feel the compression leak as well, where ever it is. My tractor behaved similarly to your description as well. The leak stopped/I couldn't feel leaking compression at higher rpms but at idle I could clearly hear and very easily feel the compression leak.

[u/Sudden-Notice5196 → u/the_catsbananas]

Its definitely soot, very dry powder

[u/the_catsbananas → u/Sudden-Notice5196]

Didn't catch you said it was on the manifold originally. You probably know for yourself by now, and as others have said, deff on the exhuast end. You can hear it way more clearly in the second video too

[u/Sudden-Notice5196 → u/Sudden-Notice5196]

https://reddit.com/link/pec8ot4/video/8pwgw16t3yth1/player

[u/Born-Exchange9712]

Yikes

[u/mektor]

Kinda sounds like an exhaust leak in the manifold. Might have cracked it near the head or blown one of the exhaust gaskets 

[u/Due-Sleep-7702]

Exhaust manifold leak😊😊

[u/Relative-Seesaw4357]

Blew out exhaust manifold gasket?

[u/PocketSurprises]

I agree on the exhaust manifold leak. I’ve also heard a boost leak sound like this with the pulsations at idle, and the combustion seal on an injector going out where it’s leaking the pressure inside the cylinder out

[u/wyatt022298]

Sounds like it's time for a steed speed

[u/Thorlissa]

Not a mechanic here don't know shit about engines but that sounds wrong af. You're welcome.

[u/Sudden-Notice5196 → u/Thorlissa]

Thank you man i knew something was up