I recently noticed a strange condition that has me stumped. Blazer drives and idles at the correct temperature, however after I run it hard (on the interstate) I’ve found that after shutting the engine off and then cranking it again minutes later the temp gauge reads slightly hot. In addition, when this happens and I get back out on the road my radiator fan runs harder than normal and the acceleration is weak until I get up to speed, at which point I regain power and the excessive fan noise goes away. I’ve checked the radiator for leaks, done a good flush and replaced coolant, and replaced the thermostat. Not sure exactly where to go from here. Haven’t gotten any codes either. Has anyone run into anything similar? Much thanks in advance. Happy to have found this forum.

 

I've had the same thing on long road trips. Especially through the states(drive faster), I would have to pop the hood to let extra air cool down the engine before going. I think it's just that it was ran hard for so long that it's still stressed, then once at reg temps again, it goes back to normal.

Hasn't effected anything to what I can tell, and it's been like that for years for me...

 

Heat rises, heat from warmer water around cylinders rises to the heads. It also conveys to the radiator warming the thermo clutch.
Higher temps showing on gauge and thermo fan clutch running longer after a long run then shutting down engine is a normal condition due to no water circulation.
Lower power feel is a slight drag due to the fan clutch staying engauged untill it cools down, may be time for a tuneup.