which coolant sensor did you replace, the one in the cylinder head or the one in the intake? The one in the head only controls the guage, the "2 pronger" in the intake controols engine computer signal. if you replaced the one in the intake and no codes then the best possible scenario is a defective replacement sensor or hidden voltage drop. To monotor this you have to have access to a scan tool. The local auto parts store usually rents them out for free. (murrays, Autozone)(usually a couple hunderd dollar deposit) anyway, don't just get the code flasher, this will tell you only if the computer has encountered a default code. I recommend the Actron brand scan tool. It has a 3 line display readout. After pluging the scanner in, you can choose an option to "view stored codes" or to "view Data" <--or something like that. You can monitor what is happening with the engine running by scrolling through the sensors and viewing their respective voltages. Only when the sensor drops below a certain voltage will it store a code or even set the "Check Engine" light off. This does not mean that the voltage the sensor is givig off is correct... There is a manual with the scan tool software, and it lists off typical voltages and the definitions for each abbreviated sensor listed.
I found a bad TPS just by comparing the typical voltage listed in the book to mine. and it didn't set the check engine light off.
Pay specific attention to your engine temp line when monotoring the list with the engine running, this should for sure find your problem.
My 90 k5 with 190,000 smokes like crazy. It burns oil, coolant and sometimes gas!!!, it has never stalled on me though, unless an electronic sensor was bad.
Good luck.
Jeremy /forums/images/graemlins/usaflag.gif
