what is it for?? is it needed? Can it be bypassed? I have a 2008 DBW and it just goes from the intake manifold to the upper or lower coolant line.

 

The coolant line comes from the IM then passes through the TB to warm the TB during cooler weather. To answer your Q: yes it can be closed or plugged to eliminate the passage through the TB. Also note that beside the coolant outlet you will see a bleeder valve. This is used to bleed the coolant liquid when air is trapped in the cooling system.

Note: When adding the Hondata IM gasket (that reduces the temp of the IM) this serves the same purpose and also blocks off this coolant passage.

 

I have a P2R IM gasket and it may block that off but there is still coolant in the line so to me there is still coolant heating up the IM....I already bypassed the throttle body coolant along time ago. I just didn't know thats the only perpous it served

 

Hondata IM gasket FTW!

 

I got the IM off last night and the P2R...maybe its a Hondata one but I can't remember. But it does block that water port but coolant still hits on the IM side of the gasket so if you really want to keep it from heating up your IM then you have to block the coolant line that either comes from the upper/lower main coolant line also or it doesn't do any good.

 

I'm not sure if I am understanding this correctly. I have the same IM gasket (blue in the picture) and by having this, that coolant line doesn't work anymore? I could just plug it on the IM side and lower/upper main coolant line?

 

thats what Im gathering...I removed the IM last night and that hole IS plugged off so fuild is flowing from the lower/upper main coolant line to IM gasket and just stopping there. so what I see is the manifold is still getting heated up by that coolant line. The only reason I see to keep that line is for the front bleeder port and no other reason.