I have a 95 mustang gt with very minimal mods. I've had the car for a couple of years and last summer it remained on the first O of normal on the gauge. This summer it's running at the M or A of normal. I have read that it's okay when it runs there, but when my at is higher up the gauge the rpms are shaky under minimal throttle. There is also a loud rattle around three thousand rpms or more. In regards to cooling I have installed a motorcraft 180 degree thermostat and ford racing water pump. The radiator has been replaced as well and have clean coolant. The other work that has been done is a new egr valve and ect sensor. I have really ran out of ideas... I want the car to run cooler so I don't experience the shake and rattle. Please give me your ideas.