one of these things is not like the other, but the listing and reviews seem to confirm it is for a base model n16 r56 yet they are not alike. no, the sensor on the original does not fit in the bleeder screw hole lol anyone have any insight, suggestions?

old unit: no bleeder screw, skinny sensor

new unit: bleeder screw and full size sensor

 

Correct. There were two different thermostats for the Gen 2 coopers. One had a single integrated MAP thermostat and temperature sensor (4-wire connector), and another design had an independent temperature sensor. You can't find the integrated type anymore. All the new thermostat versions have two separate (2 pin) electrical connectors and a pigtail harness is required to connect it.

OBTW, the sensor isn't supposed to go in the bleeder screw hole. That would be for the bleeder screw. Looks like someone's been doing a little modification. It also looks like someone has replaced the factory coolant temp sensor connector with something that's not factory.

 

So if memory serves there were like three iterations to the thermostat. The original one had an integrated temperature sensor that would corrode and fail: the fix for that was to abandon it in place and add an inline temp sensor in the elbow hose above / in front of the thermostat. Then I think there was the fix using the temperature sensor in the bleed hole, and *then* there was the final iteration with everything back at the thermostat that's the current revision. There are different pigtails depending on what you've got.

Again, this is from memory so may not be 100% correct, but the history on the thermostat revisions is fairly complicated.