i start my car in the morning and let it heat up for 5 min or so then i drive it. after i drove it for a while and i let it idle for a while it the temp guage starts to go up (like within 10 min. of idleing) why is it doing this...? thanks. oh and also my idle when im drifting is aroung 1400 rpm and drops to about 1100 every few seconds. but sometimes when im completely stopped it idles normally. i want to fix this cuz im getting and exhaust and i dont want it to be even more noticable. thanks for the help.

91 Eagle Talon TSi AWD
it's completly stock... for now. any suggestions on what to do just tell me