It seems there are 2 sensors for coolent on my
350: One underneath block on passenger side -
and one on top of intake manifold in front of TBI.
Which is what?
Thanks!
Chuck

 

The one on the passenger side of the block isn't a coolant sensor. That is the knock sensor. The passenger side cylinder head, however, houses the fan switch (which is a form of temp sensor). The one on the intake manifold is the coolant temp sensor (CTS) that the ECM uses.

 

ok so there are 4 sensors on the heads and block. the oil pressure sensor above oil filter, knock sensor on pass side block, and one in each head.

i know the drivers side head sensor tells my gauge what temp the car is at but since im getting a entire new fan switch can i do away with the sensor on the pass side head??

 

That would be the old (factory) fan switch, so yes.