from the electronic TB control to the coolant lines, there is a lot going on that I don't fully understand and I was hoping someone could demystify that.

So what is the purpose of the coolant lines in the TB?
On the Upper front side, I see a coolant line to an electronic proportioning valve.
What is the purpose of the proportioning and the variable for altering states?
What is the route of this fluid through the TB?
On the bottom front side, I see and in and out lines.
What is the purpose of this exchange/chamber?
Overall:
what is the purpose of the coolant lines?
do they have any contact with the tb position servo or mechanisms?
what are the ramifications of by-passing this (purely for educational purposes and maybe a bit for engine bay tidiness and simplicity).

 

The purpose of having coolant present at the throttlebody is to prevent it from icing up during cold weather.

Moisture in the air can build up and freeze, causing the butterfly plate to freeze up into place. Obviously that would impact engine operation.

That is its sole purpose. Not for emissions or anything else.


Bypassing it has a negligible effect. you will not notice anything from the drivers seat

 

ok well that confirms what I guessed.

So it's pretty easy to see that the bottom front side chamber runs from the water pump to the thermostat.

Now that top front one with the proportioning valve is probably the root of my curiosity. Where does that coolant line originate from? What conditions control the operation of that proportioning valve? And is there a coolant path within the TB between that proportioning valve and that lower junction chamber?

 

use a honda parts diagram to get the actual name, and go from there.


I would imagine it is some sort of thermostatic valve, so you dont get the throttlebody heated up to the operating temp of 180 degrees F

Im guessing. Mostly because its not worth worrying about. I completely understand curiosity, but Id be more curious about getting more efficiency out of the car, as that will always translate into more useable/effective power and gasmileage (less weight, better ignition timing, perhaps better fuel atomization, etc..)

 

lol, well I worry about it because if I want to play around in my engine bay and remove any part of my intake or intake manifold that I have to worry about pressurized coolant lines. Sorry, I am an eccentric person and I see a lot of metal that can be sculpted away, and added simplicity of the engine bay.

So that was a junkyard TB. I figured I would ask before I jumped the shark. Coolant lines have been removed and I have started grinding their existence away.I think there can be some beauty to the intake if it is just properly simplified enough. So that upper proportioning valve actually has a 90 degree bend and runs through the upper intake manifold. I have to assume it exits somewhere from it but I haven't seeked it out yet.

I'll post some photos as I go. feedback is encouraged.

 

This is kinda cool.

I'd think 13fit is probably right and that valve is thermo controlled to shut at a certain temperature. No point running hot coolant through the TB, at that point it'd be de-iced already.

I wonder if it runs to the block through the manifold?

 

ya if anyone else has any insight on that upper coolant thing, please chime in. It looks like it runs (albeit its a very small passage) into the plastic manifold.

This will be the last I'll post here of what I'm doing with the TB because it deviates from the folder topic. But just to confirm, that lower chamber goes no where. I chopped it out and now begins the meticulous task of sculpting it out. Then I'll move on the the other depricated mounts and excess casting. Like I said, I've done this before and there is no purpose to this exercise.

excess parts


rough chop


entering a world on minitude

 

I guess if you follow through with this sort of thing, grinding off extra bits and casting errors, you will eventually end up with maybe 5-10 pounds of weight loss.

Is this sort of OCD really worth it?

Im not trying to be rude or disrespectful, but this is just a Fit lol

 

I remember a company that released a bypass hose and a few plugs to block off water from going into the throttle body in hopes that it would gain power. They wanted $50 for $2 crap you can get at any autoparts place.

Personally the water lines work good for rerouting and using to cool a turbo.

 

For the moment, you can simply use a double sided barb fitting for 1-2 bucks. You will ahve that hose there, but at least you will not be heat soaking your throttlebody anymore. Not that it makes a noticable difference, but that is one less thing radiating heat into the engine bay.

 

I have the coolant lines to the throttle body bypassed. Stays cool now it used to be hot to touch. Cant feel any difference obviously as we drive 1.5 liters but makes sense as cooler air into engine= more efficient. I would love to post pics as well as other mods ive done but still cant figure out how to post pics. I guess you have to upload to some site, copy url, and put in here. That's crap. Id like to upload straight from phone.

 

you can register at photobucket, and you can upload from your phone or computer directly

Just be aware it does not like uploading more then 2 or 3 at a time unless you have a spectacular internet connection. I have a 2 meg upload rating and it errors out 100% of the time if I try uploading 5 in queue

 

You can also go create an "album" here at FitFreaks; "Albums" is one of the links at the top of the forum, and it is fairly self-explanatory what to do from there. (Don't be misled by the "Gallery" link in the FitFreak header above the forum header; it is something entirely different. No, I don't know why they have both; I'm only reporting what i observe.)

 

I both hate and love hearing that comment. Yes it is an economy car that doesn't deserve that kinda attention... But with that said, we both have some very interesting race teams and people very deep in the import scene. Half the fun is having a car you should dismiss because its not a mustang/supra/etc. Having spent the past 15 years building up a racecar that is equally dismissive, I enjoy those comments when later I gain distance in every corner against a lotus. But also there is a point you quickly hit that those small savings are impossible to find and you resort to the ounce-here-ounce-there strategy especially when free-ish.

The other half of it is, (other than this being a meditative like task where I drink beer), I learn a heck of a lot about the car in the process. I mean really, if its purpose is to prevent the tb from sticking, I'd imagine that the most critical moment for that is trying to start the car after its been sitting overnight in subzero where the coolant is of equal temps and makes zero difference. And hen it's up at running temps, I'd imagine the engine bay itself is warm enough to counteract any issues.... I mean it gets frickin hot regardless of outside temps. Maybe that's just me doing some critical thinking. More than likely, I think its the prewarmed air temps that very moderately improve Honda's CAFE rating but don't translate significantly to the end user. Regardless, there is a reason.


I'll get off my soapbox because I'm writing this from my phone. I really don't like the idea of bypassing lines with a barb because it defeats the purpose and I'm pretty confident that the coolant system will be just fine without those dinky lines transferring any volume. In the past I've just kinda clamped a bolt in a strip of hose into a strip of hose till I got around to getting the source ground down and professional welded up. I don't own spares of these parts yet and wouldn't mind feedback of cleaner interrum solutions. I don't know I'd this is a trustworthy option but I did a super quick search today (if others are interested in this option, I'd gladly offer up some kits near cost because of minum order quantities). Ugh can't paste from my phone. Sorry. I think I googled for coolant nipples.

 

Car shit is about having fun. If you're having fun and enjoying doing it then of course it's worthwhile. It doesn't matter what car it is.

It's not like he's paying someone to do it.

 

I understand the fun part. I guess Im stuck being busy 6 days of teh week and 8-14 hour days.

Guess Im just being envious and an asshole lol

I wish I had a few hours a week to turn wrenchs, I bet getting rid of casting flaws and various unnecessary parts could total several pounds of weight removal.

EDIT I suggested the barb bypass method because I myself am not sure if the soolant system needs those hoses to still flow.

Perhaps a shorter hose that gets rid of that extra length, and still allows proper flow? Like I said, not sure about it.

 

well here is an interesting fact.... that "upper proportioning valve".... ya I'm pretty sure that is actually an idle air controller. I made a dumb mistake, that is not a coolant line to it, it is a breather line and it feeds into a gully in the intake. Yup, that would not be an optional part and I just trashed a TB. Lessons were learned on this, glad I have one more spare to play with.

 

when in doubt, have spares.

lol, that saved ya

learning experience

 

This whole paragraph is me all the way so I totally understand you.



Not during start-up would it cause a problem. It's steady driving with ambient air temps coming into contact with the throttle body (with no coolant going through). This is where a problem could occur in a cold climate. During this state, you could have build-up at the throttle plate and when letting off the accelerator, you could still be accelerating. Or even worse, go full throttle and a piece of ice that already built up gets lodged in the throttle plate. Again, this is a possibility in a cold climate (Ex: Alaska, Canada, etc). This may not apply to you.

 

hmmmm, so thinking this out.... I might be able to get away with this mistake by extending the IAC wiring and tapping the IAC into the valve breather line. It'd be enough to keep the idle motor happy-ish even if the entry point into the intake plenum for the valve breathers is less ideal (who sits the motor at idle anywhays??). I am not going to toss V1 for that mistake because it could potentially be used later to test a more extreme option (and hide a whole lot of more plumbing).

With the TB, I'm starting again just removing the coolant lines. I picked up a metal intake manifold and will start having fun with that. If I can get another at the right price, I will and I'll make an EGR free version and if it can test out OK, I'll send it out for extrude honing. I figure if I can get the car that far, I'll be ready for some much more significant and dedicated mods. Lets call it future option scenario.

The other half of this work, is being invested enough in the car and liking it enough to keep it for a while. I won't sugar coat that professionally it appears below my means (especially in base trim). It needs a few very clean looking outwards improvements and a major interior overhaul. But more important than that, I need to establish a personal connection to the vehicle (wait till you see what I do when I get some spare door panels). I'm going to do a month or 2 of building up a certain amount of cash free repertoire with my car and then dive into the interior.