What is the sensor underneath the trottlebody?
 

I am having my throttlebody bored to 53.5mm and was wondering what the sensor was on the bottom right side of the tb. Reason why, I know alot of people are bypassing the coolant to the throttlebody and was thinking of making a plate to do away with the little housing on the bottom of the throttlebody since I would not be using the coolant lines anymore. Any problems associated with bypassing the coolant lines?
Thanks
Chad

i think it is idle air control.

That is the idle air control valve, and it is installed into that coolant passage, so you will need it.

All right. When people bypass their coolant lines to the throttlebody what do they do about this sensor?

Sure it isnt the Throttle Posistion Sensor ... i forget which one is which off the top of my head and i aint ogin outsdie now at 1/4 to 11 to check it ... but the Throttle Posistion Sensor is a round plug with 3 wires in it, Blue, Black and ???

<--- Self proclaimed Throttle body expert

Bottom of the throttle body is the IAC and the routing for the coolant. The TPS is on the side of the throttle body, obviously working off the throttle shaft. You need both of these, so they both stay on :)

Be careful of bored throttle bodies. Not many people know how to do it properly.

-Shannon

From shoebox site
http://csce.uark.edu/~jgbertr/rb/iac3.jpg

See those ports on that bottom plate, to do the coolant bypass, people just pull the hoses off and route them together.

The IAC sensor is the one I'm talkin about . Thanks for the responses everyone. The question I'm asking is once you pull those hoses off and splice them together how does this affect the IAC sensor. Correct me if I'm wrong but is measures the temperature of the air passing through the throttlebody.If i relocate it will it throw any codes or crazy readings.. And since there is no longer coolant passing through it the entire bottom housing could be removed and replaced with an aluminum plate and the IAC sensor could be relocated to my ram air box or something couldnt it.

You may be confusing the IAT (Inlet Air Temperature which is in the intake elbow) with the IAC (Idle Air COntrol).The IAC just happens to have been packaged with the coolant lines in that plate. It opens and closes to control your idle speed. It doesn't sense temperature. IAC must stay. You can pull the coolant lines off and either put plugs on or leave them open, it will make no difference. Mike

I got ya. Right on the money mike. I wrote it wrong above. But yeah I was thinking it took temperature readings thats why I was going to relocate it and slap a plate on but I guess It has to stay. Thanks for clearing that up for me.

While on the subject of throttlebodies, what is the significance of bypassing the coolant to the throttlebody? Does this actually do anything, and if so, what?

Thanks for the link to the dyno, Injuneer.

I'm not one to like to "cut corners" when it comes to bypassing a lot of things that are set up from the factory. I figure that there has to be a reason that there is coolant flowing to the throttlebody. Are there any negative effects as to bypassing coolant to the throttlebody?

Sure.... if you live north of the Arctic Circle, you might encounter throttle body freeze up, when the moisture in the air condenses on the blades and turns to ice. Otherwise, no problem.

Funny thing is, i've never even heard of it in those conditions :) I guess they would rather be safe than sorry....

Look under the hood of most GM cars. You'll find it on Saturns, etc. It's a pretty popular thing with GM apparently.

-Shannon