Exhaust manifold heat control valve.

[73chgrSE]

There's one on the passenger side exhaust manifold only. You can feel at the pipe that it is restricting flow when you open the valve by hand the flow increase.

My questions are...

Do we really need it?   Has anyone here modified it to stay open all the time?

[green69rt]

You get the same effect if you have headers.  They have no cross heat.  So yes you can just disable it.  People also use a intake manifold gasket that has no port for the heat cross over.  If you live where it gets colder then the engine will take longer to heat up (maybe).  There are probably more pros and cons and all kinds of opinions on if needed.  I ran headers, no heat cross over, in New Hampshire, Missouri and didn't have a problem.  I would think that you need to be careful how you disable it.  Best might be to take the flapper plate out of the exhaust pipe rather than just wire it open.

But, do you really want to?  It's only closed when the engine is cold and fully open when warmed up so should have no effect on how the car performs.

[73chgrSE]

I see quite a bit of clear condensation (not coolant) coming out of that tail pipe. Wondering if that could be the reason. Not much condensation comes out of the driver side at all. That valve is only present on passenger side.