Throttle body coolant bypass


Active LVC Member
Nov 3, 2020
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Anybody know of a good way to bypass the hot coolant heating up the intake charge? I'd prefer it to be easily reversible so I can utilize it during the winter and then bypass during the warmer months, although it doesn't really get terribly cold here I doubt the TB will freeze up even if I did leave it bypassed. I have a first gen v6 by the way, although all answers are welcome for others wondering about the same thing
I've done this on other cars before. Not really worth anything HP-wise, & potentially problematic for any car where it might be subjected to cold weather. Taking it out completely means you're gonna have to put it back in the cold, or running the risk of not having it in place for the winter months. Having a shut-off valve or something like it in-line could cause a similar problem once it gets cold out. Just my 2¢, with 3¢ free
hmm, it's a popular modification with LSX engines, I thought something similar can be applied here. I like taking out what I can that isn't required for my situation, ex; I've done a secondary air pump delete since it's not needed to pass emissions in my state..

It rarely gets below freezing here so it seems unnecessary to pass 200 degree coolant through the tb
...It rarely gets below freezing here so it seems unnecessary to pass 200 degree coolant through the tb

You keeps saying this, but you are ignoring that fact that the pressure drop across the throttle causes the air temperature to drop quite a bit. Throttle icing is real, and it can happen at temperatures above freezing. Heating the throttle body also reduces carbon build up there.
That tiny coolant loop only heats the throttle body. The air passing by picks up hardly any heat since it is moving so fast and the surface area is so small and smooth.

What are you trying to accomplish? What negative do you think that having the throttle body heater is causing?
Ok I was unaware of the extent of that coolant line, thank you for the information joe. If it is not causing excessive intake heat I will leave it alone

To answer your questions, I initially presumed that the intake air would be warmed by the hot coolant and was posting here to see if I can negate that through bypassing the line.
Everything the others have said is true. That being said, I deleted my coolant line (gen2 3.9 V8). I dont daily my car, it will never see cold weather. I also have the TB off enough to clean it for any increased build up this setup may be preventing. I removed it to further simplify the cooling system on my build, and I am exploring alternative TB options (some that do not have coolant component) so I wanted to get ahead of that part of the install.

Just posting here because I did do the delete, without any expectation of power, but have not experienced (yet) any adverse effects.

The 350Z/VQ and some of the Lexus 1UZ (i think) also do this mod, like the LSX crowd. I have seen shut off valves implemented to serve as a seasonal mod. I would just do away with it entirely, otherwise you just have a new part to worry about failing.

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