what is this

ok i just broke the vacuum line going to this thing. what is it? and what does it do? goes from throttle body to this. will it make it run rough?

MAP sensor and yes, it will make it run rough. Repair the vacuum line, clean out TB.

thanks!

That sensor determines the air pressure in the manifold by watching the pressure on the vacuum line. The computer uses that information in addition to a bunch of other inputs to determine how long to fire the fuel injectors. If the line leading to the sensor is damaged, the computer gets bad data and fires the injectors wrongly.

It is the single highest contributor to determine air/fuel ratio by the ECM. Gotta have it hooked up.