Strange?!?!

Hey, I have a 90 esi fwd, it runs great when its cold, but once it heats up it runs horribly without power. I replaced the thermostat, and it didnt help, i dont know why it may be running like this, any suggestions?, head gasket?, rings...i ahve some blowby....timing? any help would be awesome, i need to fix this car!

coolant temp sensor. when the computer doesnt get a reading from it it goes on a default value. check vfaq.com for how to test it

Thanks, but how do i replace it/locate it and whatnot, i know alot about cars, but im still learning about the talons.

vfaq.com the answers to everything you need. or buy a chiltons or service manual