Ok....what does the green one do?

[jteuton]

Well I was looking at thermostat housing and I see a little electrical wire going to a small adapter on the side.....I take it this is the sending unit for the temperature?.....I'm curious what the adaptor with the green plug directly on top is for. I unplugged both and the gauge quit working but thats about it.

[cruznz]

ect sensor probably

[jteuton]

any adverse effect from leaving it unplugged?

[cruznz]

assuming ur car is efi.... .....ect signal is used to alter basic injector pulse width....ecu use's this signal to adjust a/f ratio ......i.e,cold start....signal from ect tells ecu that abit more extra fuel is required for starting,.....as engine warm's up....ect signal to ecu varies,ecu sends signal to adjust injector pulse width for a/f ratio,....so....do you have a problem with it starting up on cold morning's...
hope this sheds some light.

[jteuton]

my ecu is a piece of junk

[anchovies]

the small one is the sending unit
the bigger one directly up of it is the temperature switch (try jumping it, the fan will come on!!). So unplugging this will try a code on the ecu and your fan won't come on

the ect that cruznz is talking about is on the right of the switch
hope that helps

[jteuton]

I thought the temperature switch was located on the bottom of the radiator?.....Ok.....well anyways I'm going to have some work to do. Anybody with a pic of the drain plug thats on the block?

[anchovies]

Yeah there's another one bottom of the radiator.
Don't bother with the drain plug imo, not much coolant left in it after you drain everything. Just flush it a couple of times.