Heated throttle body
- Thread starter V8MX5
- Start date
The 1UZFE EGR Delete Kit is available for sale here.
That also.
No Ed, it was sitting in the middle of the biggest solar furnace on the planet, where ambient temperatures reach 55 degrees pretty regularly, and the surface temps of dark bodied static equipment can go as high as 80. Not too far off from underhood conditions.
Anyway, here's a cut & paste from a Toyota Tech article which hopefully will reinforce the point about the throttle icing for the uninformed. This isn't 1UZ or 2JZ specific, but is from a general Toyota Tech article.
Bloody Jafa's!
...by cold, he means, about 15deg C, plus a little bit of wind haha
If your MX5 is white, i saw it at a skid comp in a velodrome in Manukau a few years back. Cool little car
Yup that was my old car. Sold it a few years back. About to build a 2000 model one, just getting all the bits together.
The water keeps the throttle body warm and keeps the butterfly from freezing up. In cold climates if the throttle is held in one position for a long period, with a fair amount of flow going through it, and some pressure drop across it, it can ice up. Not a good situation for trying to stop your car if the butterfly is literally "frozen" in position.
I work in the Sahara desert, and last month when it was near 45 degrees C one day (around 112F), we had a control valve ice over due to the pressure drop and gas flow across it. The gas itself wasn't that cold, but the amount of flow going through it, and the pressure drop was enough to freeze the thing.
In thermodynamics, it's known as the JT or Joules-Thomson effect, and is the fundamental principle for how all refrigeration systems work.
Anyway, if you live in a climate where it occasionally freezes, it might not be a bad idea to keep the water pipes connected, or else just not drive the car.
I work in the Sahara desert, and last month when it was near 45 degrees C one day (around 112F), we had a control valve ice over due to the pressure drop and gas flow across it. The gas itself wasn't that cold, but the amount of flow going through it, and the pressure drop was enough to freeze the thing.
In thermodynamics, it's known as the JT or Joules-Thomson effect, and is the fundamental principle for how all refrigeration systems work.
Anyway, if you live in a climate where it occasionally freezes, it might not be a bad idea to keep the water pipes connected, or else just not drive the car.
E
ed_ma61
Guest
and was you control valve sitting on top of a nice internal combustion heater?
That also.
No Ed, it was sitting in the middle of the biggest solar furnace on the planet, where ambient temperatures reach 55 degrees pretty regularly, and the surface temps of dark bodied static equipment can go as high as 80. Not too far off from underhood conditions.
Anyway, here's a cut & paste from a Toyota Tech article which hopefully will reinforce the point about the throttle icing for the uninformed. This isn't 1UZ or 2JZ specific, but is from a general Toyota Tech article.
E
ed_ma61
Guest
oh yes, its for throttle ice management, no question....
utility for 95% of users though? to the uninformed it seems youre suggesting that the whole world needs to be scared of deadly ice buildup
utility for 95% of users though? to the uninformed it seems youre suggesting that the whole world needs to be scared of deadly ice buildup
Ed, no one but you has used the term "deadly ice buildup", but stopping any car with a stuck throttle isn't much fun, especially if it's a heavy sedan, with A/T, power brakes, etc. in freezing conditions.
V8MX5's question has been answered; he now knows why the water lines are there, what their purposes are, and what "can" happen if they're not connected, so he can make an informed decision whether to connect them or not.
Probably many of us here have disconnected them, and hopefully, will never see stuck throttles, but there are areas of the US, and probably in Oz too, where frozen throttles could happen. As we don't know where V8MX5 calls home, I think it's better that someone gets the full picture in order to make an informed decision.
V8MX5's question has been answered; he now knows why the water lines are there, what their purposes are, and what "can" happen if they're not connected, so he can make an informed decision whether to connect them or not.
Probably many of us here have disconnected them, and hopefully, will never see stuck throttles, but there are areas of the US, and probably in Oz too, where frozen throttles could happen. As we don't know where V8MX5 calls home, I think it's better that someone gets the full picture in order to make an informed decision.
gmacrae
Member
Well, i've learnt something. Jules Thomson is responsible for the deadly ice buildup killing millions on our roads. That bastard. :biggrin:
Still, with the engine keeping it warm, i imagine a 1uz throttle would have to be running well under freezing ambient temp to ice up (like 10below). So if you live somewhere that sometimes gets snow it would be smart to leave it hooked up.
Still, with the engine keeping it warm, i imagine a 1uz throttle would have to be running well under freezing ambient temp to ice up (like 10below). So if you live somewhere that sometimes gets snow it would be smart to leave it hooked up.
Thanks for everyones replys. I live in Auckland, New Zealand. Its pretty dam cold here, winter at the moment and it does snow down to ground level in variuos parts. Being in auckland it doesnt snow but it can be pretty cold most of the year. I have decided to connect up the water lines on my throttles.
The throttle body won't see true ambient temp.
Due to the wind chill factor of the air moving through the throttle body the actual temp at the blade can be much lower than ambient.
This gets worse as humidity rises. Think the cold of winter driving in rain or (worse) snow and you can well see you will get way below freezing temp at the throttle blade.
We do have icing problems here in Australia as we have some ptretty cold areas during winter. It snows in more places than just the Snowy Mountains!
Due to the wind chill factor of the air moving through the throttle body the actual temp at the blade can be much lower than ambient.
This gets worse as humidity rises. Think the cold of winter driving in rain or (worse) snow and you can well see you will get way below freezing temp at the throttle blade.
We do have icing problems here in Australia as we have some ptretty cold areas during winter. It snows in more places than just the Snowy Mountains!
gmacrae
Member
Bloody Jafa's!
...by cold, he means, about 15deg C, plus a little bit of wind haha
If your MX5 is white, i saw it at a skid comp in a velodrome in Manukau a few years back. Cool little car
E
ed_ma61
Guest
a reasonable proportion of factory vehicles come without coolant ports in the t/b's. near zero of all aftermarket throttle bodies have that provision.
My guess is Mr Toyota put it there because he thought it was needed.
I can't see him spending the money to do it if it wasn't needed.
Maybe the UZ is prone to icing up? Who knows.
I know my aftermarket T/B doens't run cooling but I don't drive my car in the cold as I'd freeze before the throttle blade!
I can't see him spending the money to do it if it wasn't needed.
Maybe the UZ is prone to icing up? Who knows.
I know my aftermarket T/B doens't run cooling but I don't drive my car in the cold as I'd freeze before the throttle blade!
Bloody Jafa's!
...by cold, he means, about 15deg C, plus a little bit of wind haha
If your MX5 is white, i saw it at a skid comp in a velodrome in Manukau a few years back. Cool little car
Yup that was my old car. Sold it a few years back. About to build a 2000 model one, just getting all the bits together.
XR8tt
Active Member
Chill factor seems to happen when there's some evaporation..
As in alcohol / Top fuel cars.. The reason they spray inlet hat after burnout.. There are injectors in hat, cooling through evaporation takes place..
In cold areas it's usually very low humidity so icing would be rear..
In the carb days !! Yes it was an issue.. The old VW beetle engine has two exhaust ports through inlet.. If these are removed or damaged?? They will def freeze up..In short time too !!
Yes it would stop freezing and Toyota would do it to 100 % safe as they can..
In some cases they are fitted to COOL in throttle body as some engines have EGR running through inlet near throttle body..
As in alcohol / Top fuel cars.. The reason they spray inlet hat after burnout.. There are injectors in hat, cooling through evaporation takes place..
In cold areas it's usually very low humidity so icing would be rear..
In the carb days !! Yes it was an issue.. The old VW beetle engine has two exhaust ports through inlet.. If these are removed or damaged?? They will def freeze up..In short time too !!
Yes it would stop freezing and Toyota would do it to 100 % safe as they can..
In some cases they are fitted to COOL in throttle body as some engines have EGR running through inlet near throttle body..
