Coolant steam coming from underneath exhaust manifold (or possibly an exhaust leak?)

[oldmansupra]

After my 7mgte warms up, what I'm assuming is steam from coolant boiling comes up from underneath the exhaust manifold in the CPS area. I'm not sure how to identify it, whether it's an exhaust leak and I should replace my exhaust manifold gasket or whether it's a coolant leak. I'm assuming from my recent work that it's coolant related though.

Recently I have:
- taken apart the intake manifold side of the engine, draining coolant from the hoses
- Replaced the CPS. I have a timing light but haven't been able to time the engine because i can't get the idle below about 1200 to 1400

Since the coolant leaked out from various hoses in the system i have filled it up, squeezed the top hose, filled it up etc. Let it run, filled it up... and it stays at a constant level now.

What I have planned to do next is:
- Raise the front of the car, letting it idle in the air and keep filling the coolant up
- I also have brand new coolant hoses coming in to replace my old ones
- Possibly replace my radiator cap if that could be a problem

I've been reading that incorrect timing could cause this as well, and my car needs timing since I just replaced the CPS. I'll have to figure out my idle first though which is a problem of its own. Any suggestions are appreciated.

 

[Late]

Did you by chance spill some coolant on the engine and it's just burning off after the engine gets warm? I know I had an old hose burst and got coolant all over the back of my engine and for a few days after the engine would smoke.

Just a thought.

 

[oldmansupra]

Yeah I thought about that and I did spill coolant in that area. It just seems like a lot and I've let it burn for around 20 mins and it's still steaming

 

[Chaingun]

if your timing is off your idle will be all kinds of screwy, try timing it first to avoid preignition that can damage the car, this should help you get your idle into check, it should be between 10 to 13* BTDC mines about 11* and i idle at 700 rpm.

 

[Suprabeast4x4]

Head gasket leaking coolant exterior by chance? Just my thought. good luck
I hope it is just spilled coolant for your sake.

 

[oldmansupra]

Yeah I'd like to check all other possibilities before I look for that because it has a mhg and arps with 15, 000 kms. Can I time the car if the idle is high? I was under the impression I had to get it down to 700 before I could set base timing

 

[Chaingun]

Right after i finished my HG and rewired the CPS i installed it and it was idling high because the motor was firing at 0*(TDC) one i hit it with a light and changed the timing to 10* it brought the idle down to normal ranges, you just have to jumper the two points in the diagnostics box and loosen the CPS, once it's loose you can start it and adjust the timing to the proper specs and you should get close to the normal idle, as the idle in these cars in 100% computer controlled that's the only adjustment we have that i know of.

 

[oldmansupra]

Okay thanks for the advice, I'll get out my timing gun and give it a shot. I heard a rumor that the early throttle bodies have an idle adjustment screw that was permantly sealed in the later years, but I'm not sure about that.

 

[Poodles]

Right under the CPS? There's a 90 degree hose right there. If it's missing it's heat sheild and/or you're missing the heat shield on the manifold, it will quickly fail.

 

[oldmansupra]

I'll double check that hose and the heat shield. Where it's coming from is underneath the exhaust manifold by the front most gap. I can't see far enough down to spot the source. I've tried to get a mirror down far enough to see where exactly it's coming from, but it's just a difficult place and the engine gets pretty hot to be reaching around.

 

[Chaingun]

theres the thermostat housing gasket there too, mine showed signs of a leak when i rebuilt the top end, as well as that hose needed to be replaced

 

[oldmansupra]

I removed the intake manifold from the car right up to the head. I had the coolant hoses disconnected there and coolant leaked into the manifold and down into the head. I'm thinking this smoke is my engine burning the coolant off, does that make sense?