first post on this site....been reading w/o writing way too long

ive been looking through the service manual pdf's for the last few days. I found that the tc has a heated throttle body. i decided to remove it and see if i could notice a difference. anybody that has any engine tinkering experience can remove it. I removed the entire intake and battery to make the area cleaner. Simply rerouted the coolant lines back into themselves to create a loop. I dont notice any difference in +40F weather but there is definantly more power in the closer to freezing temps. Obviously, dont remove the heating if your car is driven in freezing climates very often. Frozen stuck throttle bodies arent fun lol.

just thought i would give some guys a good after work project good for .01hp

 

forgot to post....

this should be common practice for anyone installing a CAI. no point in going after colder air if you are going to warm it before it gets to the cylinder.....

 

Put some pics up! How much does the heating actually effect the intake temperature?

 

Inducion ice shouldn't be too much of a prob. here... but can form when the temp/ dew point spread is less than 11 deg c ... so when i did mine, i put in a by-pass with valve, so that throttle heat can be applied if needed. - just a thought

 

a valve would be the best way, yes. i live in central cali so there are all of about 2 days a year i have to worry about. I have taken the car through snow and ice since removing the heat and had no problems at all.

i will try to get some pics up soon....

 

That has to be the dumbest thing that I have ever heard. The Throttle body is obviously heated for a reason. Actually I really wouldn't call it heated. It helps WARM up the throttle body quicker during cold startup. This would reduce condensation that could form around the plates and create that nasty black buildup that I am sure you have all seen. Noticing a difference in power at any temp... I dought it! I word of advice would be to leave it alone. Keeping the trottle body and engine at the same temp also increases gasket life, reduces distortion, and helps to reduce emmisions.

 

it may be the dumbest thing you have heard but is actually common practice among classic car crouds. you are correct in saying that it is there to "warm" the TB. this is just to comply with emmission laws that cars must come up to operating temperature sonner . Since the TB is not connected directly to the engine, like most engines, you dont have to worry about the gasket. further, the intake man on the 2az-fe is a plastic-glass composite material and gets only warm to the touch even under operating temps.

I agree with you about the power gain. unless it is very clod outside i dont notice a diff at all....none. under 40F the response seems to have improved greatly and pulls from 5500 to 6500 stronger.

 

well if you do develop problems, don't think scion is going to cover that under warranty.. lol.. and it's not like you can put the parts back in to heat it up again and take it in.. techs would realize what happened.. but hey if you want power.. why not just get a supercharger?

 

I didnt have to remove any parts so I dont think i will have any trouble putting them back on. The coolant is simply in a loop.

I will be getting the supercharger after it is made available to purchase.

 

Induction ice doesn't form during start up, and is in almost never a problem in fuel injected motors. Carb. engines had problems mostly due to the vaporization of fuel in air, cooling the air to the point of freezing. ALso, the bernuelli effect lowers the temp. up to 70 degrees at full throttle. In theses cases, Ice can and will build up in the throttle body if there is enough moisture in the air. Especially when the throttle is then closed presenting a cooled sureface directly to the airflow. By warming the throttle body, you eliminate the possibility of induction system icing. As i said before, the is almost never a factor in Fuel injected engines, because they need no pressure changes to draw fuel into the airstream. If gaskets couldn't seal with this little of a temp. difference, then we'd all be screwed. as far as injesting water on start up... a little condensation isn't gonna hurt that much... did you know gas has water in it? somethin like .2ppm.... if they were worried about it, they would have to heatt he whole intake. If you pay attention to your temp / dewp point, TB heat is only needed when the temp/ dewp. range falls between 7 deg c, and the outside temp is between 10 - 20 deg C.