Bleeding Air From Coolant

[silviaz]

1 hour ago, GTSBoy said:

Yeah. One on the back end of the plenum, on the IACV, and one on the front end of the plenum. They are both plainly visible.

Ah right, cheers for that!

[silviaz]

1 hour ago, joshuaho96 said:

IACV has an air bleed plug in this part of the engine manual. I'm guessing if it isn't bled it will cause weird idle behavior as the cold start valve won't get hot enough to close properly at the usual rate. 

Ah right, cheers!

[GTSBoy]

1 hour ago, joshuaho96 said:

Kind of surprising, with cars this old I've seen a lot of them suffer from high idle due to internal vacuum leak. Fuel trims look fine but the cold start valve just wore out from all the heat cycles and won't close up all the way.

That's a whole 'nother issue. Nissan ones get dirty and sticky.

The coolant heats the wax pellet thingo to close the valve, so it is open when it is cold. And so if there is no coolant it just takes longer to close, because the heat has to soak all the through the inlet manifold.