Head gasket failure?

[turbowrenchhead]

I thought I was experceing a crossfire miss. I had a miss under load and it would clead up after it got past 10 psi of boost. I changed the wires and plugs tonight and it is worse. Now it misses terribly under a slight load and takes longer to clean up and sometimes it doesn't. I was just about to drive it back in the shop and my temp light came on. I open the hood and the overfull is full of coolant and bubbling. I thought it was going to blow the cap right off so I closed the hood. I wonder if the head gaskets blew and thats why I'm getting a miss.
I did drive it a little while back and it backfired or severally detontated and thats when the miss started occuring. I was having a hard time getting my boost to be constant it wanted to creap and thats when it backfired on me. Ever since then it hasn't run the same. But then when I picked it up a week later from the tranny guy it ran good and the boost stayed up. I still am having a problem with it diseapering. I even uphooked my accutator and tightened the hell out of it and my boost still goes who knows where. Maybe out the head gaskets and into the coolant system.
I just had the fu**ing motor out and put cometics head gaskets in it with head studs. I would hate to think they are bad already.

 

[turbowrenchhead]

I unhooked the vacuum line from the wastegate and tightened the rod the boost would still vanish. So I was thinking that the exhuast was overcoming the spring pressure in the accuator. I wired the wastegate shut and no boost diseapring act. I also reposioned the flange on the exhaust housing thinking that the puck wasn't lining up right. After I wired it shut and it was steady. I still have a miss though. So I am thinking that maybe the accuator is internally sticking. So I srayed some lubricant up in there and hooked up a externall boost supply and accuated it a few times. It seems to be fine now. That would explain the intermitent/inconsistent vanishing act. I still have a miss under load so who knows. Maybe I have to go to 10 mm wires. I got some a/c delco 8 mm wires today. I thought that would fix my problem. I guess now unless the miss is from something else. But I don't have any clue from what.
The antifreeze problem seems to be fine. I think I just got her too hot from a bunch of short trips and it boiled over. Or my t stat stuck.

 

[cool 84]

So it idles fine? Usually a compression loss shows itself at idle and gets better with boost. What are the plugs gapped at? I chased down a problem similar to yours for a year and fixed it by gapping the plugs down to .030. The more power you make and more boost you run, the narrower the gap has to be. When mine misfired/popped it also blew headgaskets so be careful.

Could the boost going away be a symptom of your misfire? Not enough exhaust volume/heat to spool the turbo?

Also, at your level of mods, why play around with boost problems. Get a good external gate and have rock steady boost everytime. Don't risk your motor. I got a good deal on my gate, maybe I can get the same deal for you.

If you're still suspecting headgasket problems, don't run antifreeze right now. It eats away at the bearings, even while the car sits.

 

[WFO]

wait til it cools down and check your coolant level.i had this problem recently after changing my waterpump gasket.my coolant overflow was bubbling and i was crappin my pants thinking i had a blown headgasket.turns out the radiator wasn't full and was pushing air into the overflow.as soon as i filled it up all the way no more bubbles .

 

[turbowrenchhead]

Well I put the t link on it later tonight and come to find out the cooling fan wasn't coming on at all. This would explain my temp light coming on and overfulling of coolant.
I believe that the boost vanishing act is cause by a sticky accuator. I spray a lead free greese in it and it is alot better. It did do it twice since then but not as bad as it was before.
I still have a miss under load. It seems I have to put it to the floor and let it go. When I get above around 10 psi it cleans up and runs really good then. But from about 5 to 10 it runs like sh*t. So I can't see it being an ignition problem. The wires and plugs are new as of today and the coil was new when I put the motor together in June. I gapped the plugs at .32. Is that too much, I can't see a big differance gapping them another .02. Especially when it will take me an hour to do it.

 

[turbowrenchhead]

I called ans and caspers and described my problem. They both said try the ingnition module. I have a friend that lives close with a 84. I'm going to try switching them Saturday and see what happens.