[sd_iconoclast]

A friend of mine has a 94 Corsica with a 3100.
He failed a smog test with codes 76, 77, and 78. These codes indicate all three solenoids on his digital EGR valve were bad.
I took off the EGR valve to see if it had carbon build up. Instead. the entire passage under the valve, going to the intake was full of goo. It looked like oil and water. I could see this same goo, although less of it, in the tube going to the exhaust manifold.
See picture. I actually took the picture after I had removed alot of the goo. The passages were completely full to start with.
I cleaned it out as best I could, but the goo and the codes keep coming back.
I cannot figure out where this stuff could be coming from.
What could be the problem here?

[1988GTU]

Lower intake or Head Gasket leaking and recirculating the "goo" in through the tube and manifold. Pull off the oil cap and shine a flash light down in teh valley. Look for that same "goo".

[sd_iconoclast]

Originally Posted by 1988GTU

Lower intake or Head Gasket leaking and recirculating the "goo" in through the tube and manifold. Pull off the oil cap and shine a flash light down in teh valley. Look for that same "goo".

I tried that. I can see no goo through the oil filler cap. I also cannot see any goo in the oil.
While I admit I am at a loss, I do not see how this would do it. A leaking lower intake or head gasket could account for the goo in the EGR passagem but how would the Goo get into the EGR tube on the exhaust side?

[1988GTU]

Originally Posted by sd_iconoclast

but how would the Goo get into the EGR tube on the exhaust side?

Condensation from the exhaust.

[IsaacHayes]

thats more than condensation....

[Andromeda451]

Driver,

Make sure the engine is coming up to operating temp properly. Check the thermostat for correct opening temperature. Don't rely on the dash gauge as they are not accurate enough for diagnostics. It sounds like the engine may be running too cool to properly boil off moisture and combustion products.

Rgds,
Andromeda451