In the intake

[TT91]

a black coating? was it oil?

 

[Mark89Notch]

I took off the upper intake and found a black coating on the inside of the lower intake. I traced it back to the throttle body. What would cause this and how can I clean up the engine? It didnt look like carbon build up. I changed the PVC valve, plugs, wires, cap and rotor.

 

[stang22]

Are you using a cold air kit? Maybe oil from the air filter after you clean it up? Could be...

Tim

 

[89lxsport50]

that is normal

 

[Mark89Notch]

Yes, I have a cold air kit.
Should I put a gas treatment in the gas tank? What kind is the best?

 

[Michael Yount]

Over time, the pcv system will pull oil into the intake system - both directly into the intake via the pcv, and through the throttle body to valve cover line - which is also part of the pcv system. Nothing to worry about as long as it's not excessive.

 

[blackstangt]

Isn't the line to the heater lines, and that's antifreeze, also the black buildup, if not oil, is probably from the egr, kinda like the inside of an exhaust piece, the intake cannot escape a buildup of carbon if equipped with a working egr.

 

[dastang2]

gas treatment won´t help as it won´t come in contact with the intake

 

[Mark89Notch]

Its not excessive so ill just leave it alone. I would really like Santa to bring me a new 400hp package this year.