cooling issues

ok i have searched and searched but cant figure it out. i have a 92 4.0 that the temp doesnt stay steady its been around the 160 ish range with my ir gun to double check the gauge. i have a zj hd fan clutch 193 tstat new coolant new water pump etc. rad is about 3 years old or so. got tired of being cold so i did a heater control valeve delete on it and now its stays at 210 when driving but goes back down to 160 ish when stopped. im stumped any ideas?

i wouldnt worry about it because its not over heating and taking the heater core out gives the coolant less time out of the engine. you mite also have some air in the system. but i really wouldnt worry till it hits that 260 mark

during the summer it does occasionally hit pretty close to that mark. no air in the system i purged it all. i dont wanna be that guy on the trail this summer

the heater core is still in the loop just doesnt have that valve on it one hose off the water neck to the core and one back to the water pump heats great now

The 4.0L is designed to run between 190-210. Any higher, or lower... means something is wrong. On the bright side, it's better to run cool, than to run hot.

i know that they are designed for that and lower temps really kill gas milage and cause other problems i dont really want. no oil or gunk when coolant was flushed. is there something i could be overlooking?