3RZ engine problems; cylinder head removal

Let's start with a picture of the inside of the valve cover. Does this look like it has a blown head gasket? I didn't see any signs of coolant and oil mixing when I drained the coolant and the oil.

 

Looks pretty normal

 

To clarify: I was wondering if the lighter brown oil has coolant in it.

 

I can’t tell if that’s light brown coolant or just thin oil film on aluminum.

 

Help diagnose the problem(s)?

More information:

Had an idle air control (IAC) valve error code (P0505) a month or two ago; it was running fine, so we kept driving it.

Someone else was driving it when it started smoking or steaming out of the exhaust pipe, was running poorly, and the water temperature went high (didn't overheat). I didn't see any signs of coolant and oil mixed when I drained the coolant and oil. Compression check seems good. Spark plug threads are pretty dirty, and one seemed to smell of gasoline (not sure). I ran the engine for several minutes and there was some (not a lot of) smoke or steam coming out of the exhaust pipe.

I'm almost ready to pull the cylinder head off (I had another 3RZ that had a crack in the #3 cylinder bore, a cracked head, then blew a head gasket a few years after fixing all of that, so I'm biased toward it being one or more of these problems). The replacement exhaust manifold is cracked and broken, so I'm looking for a 2001-4 "mini header" exhaust manifold.

 

I just rubbed some of the gunk off and I had to scrub a bit to get down to shiny aluminum; there's burnt-on oil that's a gold color covering the aluminum, so I think it's some water and/or coolant.

 

≥

 

did you lose some coolant and can't find an external leak?

 

I don't know. I couldn't see the coolant level in the radiator and the reservoir was low, but that could be due to neglect.

 

You should send an oil sample to blackstone labs, it like 20 bucks and they should be able to tell if the oil is contaminated.

 

Yeah that’s no good.

weird that it would show there and not in the oil pan tho.

any oily film in the radiator?

 

The radiator isn't oily, that I can see.

 

Can we rule out the IAC valve and burnt exhaust valve(s)?

 

How do you get the cylinder head rear plate bolts off? Or disconnect the electrical connector (It's fighting me: how does it release?) and leave the plate on? It's tough to get access to any of it since it's on the back of the head and near the firewall.