Carbon in FI intake ?

[Mac]

I'm dealing with the blown head gasket on my `94 Taurus 3.0 and I found substantial carbon buildup in the intake. I'm wondering if this could be the result of oil from blow by. There doesn't seem to be a baffle or PCV in the tube that runs from the front valve cover to the intake plenum. Being port injected I can't imagine this build up is fuel related. Can anybody tell me if this is typical, a sign of ring problems, a need for a baffle at the v.c. or what?
TIA, Mac

[Sean]

Burnt Valve maybe?

I had to get the heads worked over on a 4.3 v6 a few years ago because of a burnt valve and the intake runner for that cylinder was black.

[tomslik]

normal, not just ford specific either...

although there is a tsb for a valve cover(the frontone) and new plenum gaskets on some of the 3.0's.
does yours have a plastic plenum?

[48ford]

It's normal,Irene had a town car that did the same thing.
Just wash it out and drive it.
Russ&Irene

[SKR8PN]

It is caused by the EGR valve mostly. Clean it out before you reassemble it,and don't worry about it. Make sure you also clean out the AIS motor passages as well..........

[Mac]

Thanks fellers.

Yes, I'm cleaning everthing there and also related passages.
The egr theory sounds like the most probable -it's a uniform coating through out plenum and intake.

Tomslick: The plenum is cast alu. but, what's a "tsb" in front cover? Surely not "teaspoon"

Mac

[Mac]

tsb;

Technical Service Bulletin

Why Thankye! Just shows I'm a DIY who spends more time cookin than wrenchin. :oops:

Mac

[Glen]

I believe the TSB tom refers to is on the windstars, the valve cover was not baffled and will allow oil to go back thru the intake and soak the plenum gaskets causing a vacuum leak and setting the check engine light, most commonly seen around the 50-60k mile mark.

carbon is common as a matter of fact you will get a small ridge behind the butterfly and it should be cleaned out.