OK, this is odd....

The CTS and the IAT sensor both tested out bad, and need to be replaced. They are the same sensor, but they are NOT the same connector. Here is a pic of the more common one, corresponding with the CTS.



Notice the offset sliders on the sides. These are reversed from the other one. 

Has anyone replaced the IAT? Where did you get it, did you have connector troubles?

Or maybe I will just file off the little offending tabs....... 
Oddly enough, I was mistaken about the sensors..... OK so thats not so unusual 

I just bought 2 new sensors at AZ, $15 each, and got them home, checked the resistance and they were just the same as the ones I have... about 1.7 cold. 

So that wasn't the problem.

I don't get the check engine light anymore, but the radiator fan never switches on. It will come on as soon as I unplug the CTS. Also it *seems* a little rough starting, which is why I suspected the IAT (I also got a Code 23, which is IAT). Maybe I'm imagining it, I dunno.

Any ideas?
Still no radiator fan.

I got two new sensors from AZ - they didn't fix it. The rad fan still doesn't come on, and the new switches ohmed out the same as the old. So, the sensors have been returned to the store.

I checked every ground I could find, and they are all correctly hooked up. The ECU knows when its plugged in, because it turns the fan on as soon as I unplug the connector on the CTS.

I will keep looking thru the archives, but I would appreciate a dose of diagnostic genius 

Thanks to all in advance.