Strange title I know. I bought this truck from my brother and looking down onto the passenger side manifold I see there is a purplish section on the manifold. There is tons of oil and grime built up on this truck as it has not been washed under the hood in 230 thousand miles. I have what appears to be soot covering the firewall too. I can tell that the up pipes need to be replaced by visualizing soot on them as well. Curious if this section on manifold may signify a crack in it or if maybe it is just leaking around the flange/head joint?

 

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