ok here goes...................

My daughter owns an 01 ga 3.4 auto. It was using coolant since last winter. I would just add coolant to it. In my mind I knew it was going somewhere but declined to do anything at that point. About 2 months ago she said it was loosing power. When she would give it gas to get going or pass someone, it would just change rpm after shifting down, not increase speed. It got to the point last week when she would enter the highway, it took 1-2 minutes to get up to 55mph. Also said coolant lamp was on. My wife drove the car to the gas station and she said it got hot. I looked and the oil was milkshake. I installed head gaskets and upper and lower intake gaskets, thermostat, and fuel filter. Took it for a ride and car running like crap. NO POWER. rpm won't go over 3k? Run's like crap up to that point to. Starving for fuel? Bad coil pack? Bad fuel press. reg? Clogged cat? Going to check fuel press. tonight, then unbolt exhaust and run to see if bad cat. Idles smooth, does not start right off the bat. As long as you continue cranking it will eventually start.(not like it used to just pop right off) Also, when driving (short run)it ran 220 degrees temp. radiator thumping spewing water out the overflow. Bad temp sensor? I've got a lot of time into this already and would like some suggestions on what to look for or test. I do have a snap-on scan tool. It does not throw any codes. No check engine light on car. Thanks, Dave

ouch,

I would not run the engine at all if the oil is milkshake looking.... that prob means you have coolant in your oil which is not good.. you might of blown a LIM (lower intake manifold) gasket, that would allow coolant to mix in the oil

from the story of coolant just going away and re-adding.. it might of started as a small problem then got worse to the point it is at now... the gaskets are made of a plastic rather than steel... and the 3.4L engines run hot!

After I saw the milkshake is when I did the work. It was not driven until after work done.

Your problem sounds like it may be two fold. First, you may have air in the cooling system that is causing the overheating problems. These things are a bear to get the air out of. The other is the cat. if it refuses to rev beyond 3K then the cat may be blocked. Although the earlier statement about reving but not moving could indicate a transmission issue. I would check fuel pressure just to be certain that it is normal but do it while you are trying to accelerate as this will tell if the fuel pump is working properly. Good Luck!

Problem fixed. Cat