Ok, this is a really weird problem. I've got a 1992 Z24 3.1L with about 120,000 miles on it. The problem is that once the car warms up it won't go into third gear (it's an automatic). It will just stay in second and going highway speed it will run like 3-4,000 RPM. I already changed the transmission fluid on it becaus it acted somewhat like a problem I had before with a leak in my radiator letting coolant get into the fluid. It wasn't that. I also have had the TCC solenoid go out before, but it doesn't act anything like that. I think it could be related to pressure switches in the transmission, but I don't really know any way of checking them. Is this it or am I totally off? Any ideas anyone?