bypass, pretty simple to do......

remove the line with the EVAP port for access.......if you have the stock intake youll have to take that off too...........



loosen clamps with pliers, 4 total.......



get a rag to put under the throttle body, little coolant will come out, the coolant flows (according to the service manual...) flows from the hose going into the front of the throttle body and exist on the side hose.

bottom hose on pic, bypassing throttle body.....hose in throttle body just keeping stuff from getting in there.....

after driving, the throttle body is just warm to touch like the rest of the intake.i dont know if this gains anything, but i live in the desert, no need to keep the throttle body any hotter.

or u guys could pay for it...........

ebay item# 250267840358

lolol

you just connect the 2 hose that were going to the throttle body end to end right?

I did this to my V a while back, do it to all my cars actually. No need to heat up the TB here in Texas... don't think the TB blade will be freezing shut here anytime soon!

I've seen dyno sheets on V8 cars that picked up 6 RWHP just by doing this free mod.

I dont know if this is confusing to anyone else but I would find it easier with a couple arrows pointing to what your talking about. Because I'm totally lost.

Skim302 wrote:I dont know if this is confusing to anyone else but I would find it easier with a couple arrows pointing to what your talking about. Because I'm totally lost.

see the big a55 black hose with the white logo on it? se the silver thing its attached to? that is the throttle body. see the 2 small hoses on this side? those are the coolent hoses.

im to lazy to circle them right now

iuno bout yu guys but im lost also???i cant relly see everything also cause the pics are kinda blurryy,,

What are the pros and cons of doing this?

This is a pretty common mod; done it before, a waste of time IMHO.

In most cars there are two hoses that route coolant in and out of the throttle body for various reasons (prevent throttle body from sticking in extreme cold conditions, smog, etc.) The theory is if you don't pre-heat the TB with hot coolant you'd have a colder intake charge going into the cyclinders (colder denser air contains more oxygen) which provides more power. If this were true, the gains would be negligible. Plus, it's not taking into consideration of the engine you've got below it which is basically a big metal lump of heat generator. And, which direction does heat travel? Upward.

If anything... the coolant would draw heat from the metal TB housing as it is cycled through. That's what coolant is meant to do isn't it? too keep the engine block cooler by drawing heat from the block? Popular or common doesn't mean it's right.

There is no good reason for doing this mod. But, if you still want to: pull the hoses out of the TB and connect them together with a barbed hose connector and appropriate hose clamps. Now, coolant doesn't run through the TB anymore, hence, "bypass". Nothing complicated about it.

feloniousmonk wrote:This is a pretty common mod; done it before, a waste of time IMHO.

In most cars there are two hoses that route coolant in and out of the throttle body for various reasons (prevent throttle body from sticking in extreme cold conditions, smog, etc.) The theory is if you don't pre-heat the TB with hot coolant you'd have a colder intake charge going into the cyclinders (colder denser air contains more oxygen) which provides more power. If this were true, the gains would be negligible. Plus, it's not taking into consideration of the engine you've got below it which is basically a big metal lump of heat generator. And, which direction does heat travel? Upward.

If anything... the coolant would draw heat from the metal TB housing as it is cycled through. That's what coolant is meant to do isn't it? too keep the engine block cooler by drawing heat from the block? Popular or common doesn't mean it's right.

There is no good reason for doing this mod. But, if you still want to: pull the hoses out of the TB and connect them together with a barbed hose connector and appropriate hose clamps. Now, coolant doesn't run through the TB anymore, hence, "bypass". Nothing complicated about it.

i agree that you would gain close to nothing by doing this, but i am still going to do it because i love to work on my car and it is just another excuse to "play" with it.

while the engine is a huge heat maker, u have to remember the air going into the engine is moving pretty fast and doest heat up that much, specially if you have a CAI. every little thing helps.......you dont need to connect the hoses together on the Versa, its a very simple bypass once you look at it......

on my Lincoln i can datalog with my Sniper software on my laptop, and on an 80-85 degree day the intake temps were around 60 degrees, while out on the road of course, and the IAT sensor is just couple of inches from the throttle body, and its gets HOT under the hood of my Lincoln............

feloniousmonk wrote:If anything... the coolant would draw heat from the metal TB housing as it is cycled through. That's what coolant is meant to do isn't it? too keep the engine block cooler by drawing heat from the block?

If that were true, turning the cabin heater on should cool the inside of the car...no air conditioner required.

It's a heat transfer system, with the primary goal being to transfer the tremendous heat of combustion away from the cylinders so they don't melt. There's no combustion in the throttle body (at least there BETTER not be) so the coolant treats the TB as just another radiator and tries to shed heat there.

There is undoubtedly SOME benefit to not heating the TB, but agree that the air is moving through it so fast that it doesn't heat up much. With a conventional carburetor, the heat would help prevent icing, but don't know if icing is a problem with throttle body fuel injection. Living in a desert makes the occurrence less likely, but carburetor icing has been known to occur at ambient temperatures as high as 90 degrees F (requires ~40% humidity, though).

Ron