What's up guys I bought a engine from craigslist and when I took the intake manifold off there was a nasty black tar substance building up in the head. Is it possibly just oil that leaked from bad valve seals. Guy said it had a bad head gasket but still ran and he drove it for 2 months with the


bad gasket
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Any ideas

 

slowly leaking injectors maybe

maybe when you turn it off... they oozzz fuel and it kinda bakes it on the top of the head.

 

Well, if the owner was running full time E85, it could be the black gunk we all have reported from not running periodic runs of 91

 

Some* have reported...

That looks like coolant/oil goop was going through the PCV and into the manifold.

 

EGR/PCV mixture combined with air/water and a bit of fuel.

It will all come out if you hot tank it.

 

now wait a minute... he didnt say anything about black stuff being in the intake manifold.

OP... is the inside of your intake and intake runners all gooped up black goo also??

 

if it comes from the PCV then he will see black trails coming from the small holes in the intake manifold..

 

I agree that it could be E85 gunk.