New to forum I just bought a b16a2 and noticed that cylinder 4 and 3 exhaust valves are white and 1 and 2 are not. I was thinking it's from heat or running to lean but why only on 2 cylinders? The guy I got my motor off was running a p72 ecu which I kno is not meant for it because of the butterfly valve on the gsr was thinking that May have something to do with it any helps appreciated thanks

 

 

What intake/exhaust are you using?

All else being equal, this would indicate excessive oil consumption in those chambers, which can be caused by many factors. Reading the plugs should yield similar results.

What is the reason for pulling the manifold off in the first place?

 

possibly coolant leak into the combustion chamber crystalized the valves

number 4 cylinder is usually the first cylinder to go after an overheat messes with the head gasket..then 3

 

Stock intake mani and stock exhaust mani I pulled the exhaust manifold off because I pulled this motor from my friends car after buying it and noticed that, and all four plugs are also white he said he changed them 2 months ago and the old ones were a light brown like normal.

 

Yea I was also thinking that and why does it start at cylinder 4 closest to the water pump? I'm just trying to figure this out before I drop the motor in my teg thanks for reply I might just have to do the head gasket first.

 

Forgot that he was using a stock LS exhaust manifold not b16 not sure if there's any diff though think there same size primaries

 

Water combusting with fuel will in most cases wipe carbon off of all related surfaces, cleaning them.

I stand by an oil leak from the piston rings in that cylinder, or the valve stem seals, either intake or exhaust. A compression test could provide some information, trivial at best.

Using a light to peer into the bores, you can determine if significant coolant leakage has occurred. The face of the piston will be much cleaner.