has anyone ever bypassed the throttle body heating/cooling lines? the fitting on the bottom of the TB broke off and spewed out half my coolant. is there really a reason for them?

 

i think the main reason for the coolant to flow through the throttle body was to prevent the throttle from freezing and sticking. you can just connect the 2 lines together.

 

thats what i ended up doing.

 

They were put on the throttle body to increase performance so says Ford in their manuals.
There is no danger of freezing as there is no venturi effect like there was on the carbureted trucks. Without the venturi effect there is no temperature drop at that point to freeze the moisture in the air as it reaches its dew point.

 

I've always wondered why the SBFs got the coolant lines but not the 4.9.

 

The intake manifold on the 4.9 is close enough to the exhaust manifold so you get enough heat to vaporize the fuel without the added heat from the cooling system.
The older V-8 engines used to have an heat riser to force all the exhaust gas from one bank through the intake to vaporize the fuel until the spring got warm enough so the weight could open the exhaust to the tail pipe on that bank.
Without this the engine would not run well until it got fully warmed up.

 

Except that the EFI manifold is dry flow. NO fuel gets put in until just before the air enters the head

 

True so whats your point?

The cooling hoses when they warm the TB and the TB is bolted to the upper intake it is also warming the upper intake to warm the air to help with the vaporization of the fuel.

At least Ford thought it would.

 

then why where cold air intakes invented? colder denser air nets more power than a warm, everyone says a cold air charge is better than a warm one right?

 

To give a little more power and take your money. When you talk about cold air has more power then warm air you are talking about air density. A cubic foot of cold air has more oxygen in it then warm air.
But that has nothing to do with what we are talking about here. Liquid gasoline does not burn only its vapor does. So with a cold engine you need to get as much fuel into a vapor as possible to get the power out of it.
So you need to get as much fuel vapor and oxygen into the cylinder as possible.

That said Cold air intake systems do not put cold air in the intake unless it is very cold outside they only provide cooler air than the engine compartment air. They also say they put more air into the engine.

Also note that the EGR system puts hot exhaust into the intake manifold as you drive. This also adds the the fuel economy.

The system we are talking about is a cold engine and a cold engine needs fuel vaporization. As noted above with the carburetor engine heat riser it is only used until the engine is up to operating temperature. Also warm air is used for increasing the fuel economy of the of the computer controlled engine.

I am just trying to tell the OP why the hoses are on the throttle body not how to get more power out of it.

They are there for fuel economy.

 

The throttle heater is strictly for ice - you get the venturi effect behind any throttle. The 4.9L doesn't need it because it doesn't rev high enough to pull air fast enough to create ice. The heater isn't big enough to change the temperature of the air passing by it (not enough coolant flow/no fins) - it can only keep the aluminum surface above freezing.

EGR isn't to increase performance or economy - it's to reduce NOx emissions, and protect the aluminum pistons by reducing combustion temperatures.

CAI works with EFI because the injection pressure is enough to atomize the fuel, even if the air is cold. It wasn't effective on carbs. But it always produces better economy than warm air.

 

Have you told the Ford Motor Co. about this as they do not seem to know this and say it the other way around in their Shop Manuals.

 

if its the lines i'm thinkin of there there to help the truck warm up in the cold by circulating warm coolant through the TB. But in the summer it causes your truck to suck warm air for no reason. Needles to say I bypassed them on my old 96 with no issues

 

Got a year, model, chapter, & section number for that? I'd like to read the version you found.

 

Where do you come up with this from?
How do you get a venturi effect behind any throttle with no venturi?
I do not see where you would come up with any venturi effect with no venturi to form ice in these trucks.

Is this just your opinion?

I have seen and read about it in several manuals and books but at my age I do not remember were I read it anymore.

I know the EGR system will increase MPG as this has been tested by more than one person on the threads with it disabled and with it working.
Here is one note from the Ford shop manual.

1995 Bronco/F-Series Table of Contents
Group 03: ENGINE
Section 03-04A: Fuel Charging and Controls, 5.0L and 5.8L
DESCRIPTION AND OPERATION

“Engine coolant is diverted through the throttle body mounting pad to improve cold weather operation.”

It says nothing about ICE.

Maybe not but it does it anyway.
The EGR system does it by displacing oxygen that also ups the MPG.

This is totally wrong.

A warm air intake or WAI is a system to decrease the amount of the air going into a car for the purpose of increasing the fuel economy of the internal combustion engine.
All warm air intakes operate on the principal of decreasing the amount of oxygen available for combustion with fuel. Warm air from inside the engine bay is used opposed to air taken from the generally more restrictive stock intake. Warmer air is less dense, and thus contains less oxygen to burn fuel in. The car's ECU compensates by opening the throttle wider to admit more air. This, in turn, decreases the resistance the engine must overcome to suck air in. The net effect is for the engine to intake the same amount of oxygen (and thus burn the same amount of fuel, producing the same power) but with less friction losses, allowing for a gain in fuel economy, at the expense of top-end power.