Oily Soot in Intake [Archive] - TheDieselPage.com Forums

piersbc

10-24-2004, 12:52

I took the top off the air intake to do the air modifications of cutting the webbing out as per the tips on kennedy's webpage. What I found was that the openings on the air channel were almost sooted shut. The intake manifold was coated with this oily soot too. What does this mean? Am I in for an expensive repair?

Dvldog 8793

10-24-2004, 17:21

Howdy
With your engine running take the cap off the oil fill hole and hold your hand over it and see if you can feel pressure. The soot could be coming from the Crankcase vent that termnates in front of the turbo. If it was sooted up that bad I would think that you have allot of blow-by. Is your truck an EGR rig? If so then it could also be a fualty EGR system.
Hope this helps......
L8r
Conley Janssen

HowieE

10-24-2004, 17:59

Soot is common with a diesel. If you are not using a large amount of oil and not seeing smoke I would consider this normal.

G. Gearloose

10-25-2004, 02:25

Pretty much normal for an L56.

piersbc

10-26-2004, 12:06

Is there a way to test the crankcase vent that goes to the turbo? There's a gold part with "this end up" on it between the valve cover and the turbo. Could that be defective? I'm not using any oil between changes or at least not much.

tom.mcinerney

10-27-2004, 06:27

piersbc

search "CDR", crankcase depression regulator, see GMCTD.