TB, and my knocking revisited

[Joshua993]

So, I noticed some carbon deposits on the top of my throttle body - it was obvious the gasket had failed. I have been experiencing rather loud tapping and rough running, I set out to fix that today. Firstly, I found that all but two of my intake maniflod bolts were loose - as in I could back them out by finger. I tightened said bolts, and set in to replace my TB gasket and give it a good cleaning in the process. When I pulled the breather hoses back, I found a tar like sludge in the hoses. The TB was the same way - layer upon layer of hard black deposits. And, once the TB was off, the inside of the manifold was also layered, caked, whatever you want to call it - with said tar like substance. I am thinking this stuff has no business in there. Any thought on how it could have came to reside in there? What would be the best way to get the inside of the manifold

The good news is - tightening the manifold bolts made the tapping go away alnost

Thanks all
JT

 

[RockDoc]

The PCV valve allows somewhat oily air into the intake, and the EGR system allows exhaust back into the intake. These are where your deposits are coming from.

 

[Joshua993]

Well, I suppose if nobody has ever had it apart in 165k miles, the amount I saw would be average. I did pull the EGR, which looked like a burnt hotdog with all it had caked on it.

It's all back together and run-in, and bolts retighteded. Seems to be running ok - idling a bit fast.

 

[RockDoc]

Hmmm, I should check my manifold bolts.... added to the list.