4AGZE Missfire / Steam, BHG?

[shazeal]

My car for the last week or 2 has been misfiring on idle, and once warmed up it has a fair amount of steam coming out the exhaust. For instance tonight I drove back from work about 30 mins, let car idle no steam but putting my hand near the tip of the exhaust I could feel water vapour on my hand. Let it cool down, drained coolant, changed the thermostat, filled coolant and bleed air, once it was warm / near operating temps it starts steaming, and wont stop even about 10 mins later. Ambient temp was probably around 12-15 deg at a guess.

Im thinking the head gasket is probably got a small leak in it. Ive taken the car to a few places one (my usual place when Im too lazy to do something myself) said flat out no its just a timing problem. A week later after the timing was 100% right, everything else tested i took it to another place who said probably BHG, but would have to test for $120... no way rather just change the damn thing. Another place said its definitely blown and would change it for me for the small sum of $1000 lol, im not that lazy.

Only other place water could come from i guess is inlet manifold?

What I really need to know is what else should I change/get done to the head while I have it off? Im planning on taking it off one weekend, then putting it back on the next to allow time for any other stuff that needs doing in the middle.

Thanks

[Lloyd]

How bad is the miss? Most 4AGE/GZEs have a bit of a miss when idling.

And how much steam is coming out? Is it actually using any coolant?
Water is a byproduct of combustion so there has to be some coming out the exhaust.

Put a funnel in the radiator neck and give it a few revs from idle for a minute or 2 and see if any bubbles come out. Will give you an idea of if the head gasket is blown. Should be lots of little ones if its blown a little.

Hard to diagnose faults without seeing the car

[shazeal]

The miss is pretty bad at 800 rpm get a cough from the exhaust every second at least, at 1000 rpm its pretty mild, above that is not noticeable.
It doesnt appear to be using coolant, would it just suck it up like nothing if it was BHG, as in really noticeable?

Would the car not having a cat affect any of this? Is the first car Ive had without one and I didnt do it so I didnt have a before and after to compare.