cooling problems driving me crazy!!

[blues14]

Ok, I have replaced the Waterpump, crank fan, thermostat, radiator, hoses and of course the coolant. here is my problem. Its an 89 KAe automatic. the car is driven to work, about a 20 minute drive , with no problems. i leave work, go to pick up my daughter, wich is about a 30 minute drive. when i come back out to the car, the temp gauge jumps up to one notch from H!! then it cools back down after startup, but reads half a mark higher than it did on the way there. on the 15 minute drive back home, it starts to creep back up, so i put the climate controll on hot and blast the hot air(in 80+degree weather) untill it goes back down. the coolant does not bubble into the overflow, and the hood isnt hot or anything. the car does feel less peppy though. any ideas? cuz i am out of them. is my CTS playing tricks on me?

[Shift_Tommy]

check your engine coolant temperature sensor

[blues14]

how do i "check" it? I did change the larger sensor when i bought the motor, but i am sure that it is for the ecm, not the gauge. is there an electric fan that should kick on as well, or is that just for the a/c? is there anything else that could cause overheating? hope the sensor is just wacko.

[ricebike]

hmm, i say make sure you rule out that there are NO air bubbles trapped in the system...i think your temp sensor for your gauge is ok.

eventhough i followed FSM manual on doin this, i still had a few bubbles trapped & did what u have described during my test ride after i changed out my radiator/tstat/etc...

so i repeated the procedure w/ some different techniques i read about on this forum & the guages went back to "normal"

that electric fan is for the a/c... when button is pushed & a certain temp is reached, it should cycle on-off to aid in your belt-driven engine fan.

[blues14]

ok, so i conducted a 'test' today. instead of turning my car off when i picked up my daughter, i left it running in park. the temp gauge stayed right where it should have. not once did it raise past my normal operating temp. kinda interesting, huh? but it did still feel like it had less power than it does normally.

[blues14]

so after sitting in my driveway about 8-10 minutes after arriving at home, i turned the ignition over and it was reading almost at H, then it slowly went down to 2 notches below H, but still over normal operating temps. so i turned the the car off, waited 5 seconds, and started the car up again. Now the needle is at the normal operating temp. so does this sound like some crazy sensor/gauge problem and not an overheating problem?