Sensor?

[btolenti]

What is the sensor located to the right of my MSD box in the below picture... It seems to have three wires going to it and a plastic tube....

http://coloradok5.com/photos/showphoto.php?photo=8796&password=&sort=7&thecat=500

 

[4X4HIGH]

That is your map sensor which usually is mounted next to the TBI unit on the passenger side.

 

[btolenti]

How can that be since my Blazer is carburated?

 

[Thunder]

Prolly the torque convertor lock up switch.TC Lockup is controlled by vacume switch and speed(vss) on carbed rigs

 

[R72K5]

80-87 E4ME ESC controlled cars and trucks have a MAP sensor, some of them called another name though like MAS or something else, id have to look it up again to see.
looks identical to a MAP sensor though

that in your pic is probably the tranny lockup vaccum electrical switch though, sometimes theres another one like it on other side of firewall about there too,
started for '80-up fuel mileage crappy axle highway ratio/emisisons days along with ESC system junk

kinda hard to tell what all is in your pic, kinda far away pic to see the smaller stuff there on firewall