what is it that the coolant temp sending unit does. im assuming this is the sensor that threads in right underneath the dizzy on d16z6 motors? i have been working on my d16z6 for the past month and a half, because it has been overheating. i started with a headgasket. once that was replaced and head was resurfaced i found that my old z6 could no longer be used thanks to some idiot welding the crank pulley onto the actual crank(long story), which still over heated afterwards. i purchased another z6 and dropped it in. once that was complete, it still over heats. so i took the t-stat out, but then i realized water was disappearing from my reservoir tank, ended up being that it was leaking into the cabin via the heater core tubing(bent), so i removed the heater core and bypassed it. i was out today, and it still reaches this level
C........m.l.l......H
and no t-stat would lead me to believe that it shud be colder than this. right now it runs straight water for testing, and it does not leak anymore. the only two things wrong are the temp goes up to that level, and for some reason, at about 1500 rpm, through all gears, the car jerks back and forth while driving.
i have checked everything..radiator, fan is on a switch, hoses

would the coolant temp sending unit have anything to do with this, or could it be because it is running water, and it is heating up more than antifreeze would?

 

anyone?

 

the engine temp sensor has two different meanings my friend! One is referred as sending unit (for guage) and other for fuel injection. Based on temperature input from this negative temperature coefficient sensor...the pcm then in turn changes the fuel map... the engine requires more fuel when cold than warm......hence when these little boogers go bad they dump fuel in the engine... usually...not always...

 

btw...... water is actually the best coolant... distilled water ONLY!!! it has all the minerals that corrode ur engine removed.. u can use this with cooling system and water pump lube... Antifreeze is just that .... it has a way lower freezing point than water hence it takes lower temps to freeze and crack blocks, pop freeze plugs...etc..... take an infared pyrometer and check the temp by the temp sending unit... ur car may not be overheating... the temp sender may have shifted calibration!!! u also may have some air in the system still...