Step 4: If you are unable to remove the air ducts to expose the throttle body, stop and do not attempt this project. Let a professional technician handle the job. You may have to press the gas to help it warm up and even to keep it running. My question is do I really need coolant lines running to my throttle body in a hot climate. If the hose from the TB is connected to the water pump, their flow is actually bucking each other. After the car is completely warmed up, the hot coolant continues to run through the throttle body warming the air, and that is why we bypass the coolant line through the throttle body. Safety wiring the throttle body's fast idle cam half open 4. I am not using those lines on my 6.0, all it does is send coolant through the throttle body. I've run mine with no issues for over 4 years after learning about it on the Z71Tahoe-Suburban.com forum, where the moderator-in-chief ... Not running hot rad-fluid through the throttle body can't be bad. 2) Has anyone done this mod? That's commonly called a throttle body bypass and keeps the TB cooler. . It consists of a housing unit that contains a throttle plate (butterfly valve) that rotates on a shaft. From what I have read GM incorperated this into the throttle body to prevent any kind of freezing of the TB valve in extreme cold conditions by having water from the cooling system run through it. RAY: The throttle body is the throat through which the air passes when you step on the gas pedal. The air coming in works better if its warmer. You also want to set the heater controls to full hot to allow coolant to fill/circulate through … I had a coolant line blow. And it costs $1,000 because it's a finely crafted and machined piece of. When the problem first appeared i thought it was iacv or tps. It will cool about as fast as the rest of the engine, maybe a little faster since there is not much mass of metal there compared to the block/crank/heads. so I took off the throttle body to clean off the carbon. report. Transmission oil as you know gets hot and needs cooling, low coolant will cause some transmission problems especially under heavy load. turns out, the coolant circulates only at a corner of the throttle body (image attached- yeah thats why i said it needs cleaning ) but the assembly being aluminium, must be getting heated around the perimeter. WTF gm; why run coolant through the throttle body? This throttle valve operates like the throttle valve on a carburetor--as the throttle is opened, more air is allowed to enter the engine. From my understanding the coolant passes through the throttle body to warm it when its cold to help with the emissions. Can I just bypass them? Shakerhood beat me to it. Honda did this to prevent the throttle body … You will need to find the throttle heater hose, which is mounted on the bottom of the throttle as part of the throttle. I am going to leave that part as is, and work on the problem from another angle. It allows a higher idle when coolant temps (and therefore engine temps) are cold. The coolant flows through the throttle body to prevent Icing on the throttle plate and to ease the job of the Idle Air Control Valve by barely warming it up. save. I dont know. Where the throttle body injector differs from the carburetor is in the area of idle control. I have heard of a minimal power gain if any from it because the TB would not be warm from the coolant running through it but, the gain is not really noticeable. TO avoid throttle body icing in colder climates (38 degrees and the low pressure of the throttle body area can be enough to cause inlet icing). In an electronically fuel-injected car, a throttle position sensor and air flow sensor communicate with the computer, which supplies the corresponding … 7. A bad throttle body valve can cause a lot of different symptoms in your vehicle. I looked underneath the car and coolant was leaking onto the ground. I look into the engine and I see a small puddle of brown water?! Wouldn't that warm-up the intake air? 56 comments. There are three thing that are all connected that are important. I did a little more investigating and it seems pretty normal to not run coolant through the TB. Any info on this would be great. Here is a more detailed list of the most common bad throttle body symptoms. Its kind of buried under the throttle body, where the general vicinity of it is. WTF? The issue could also be an incorrectly adjusted throttle stop. This is no "factory mistake". The 3G flows engine coolant through the throttle body, which warms the air going into the engine. I've seen this done but I can't remember where and wasn't too sure why it was done. What are the advantages (if any) of disconnecting the coolant pipe from the throttle body and run it straight to the IACV instead? I was careful not to let any spill into the opening when I removed the hoses off the throttle body. I might be wrong but thats what I hear. It's all pretty negligible compared with the efficiency of your intercoolers. I have since put on a new intake manifold, throttle body, pcv valve, o2 sensore repalce, coolant level checked, searched for vac leaks, and the fitv was elimanted because there is no place for it on the skunk2 manifold. The coolant pipe now bypasses the throttle body 3. In some cases, both sides of the throttle body are connected to air ducts by means of hose clamps; in this case, you only need to remove one side to expose the throttle body for cleaning. Vacuum leaks can disrupt the air-fuel flow because of an imbalanced airflow, which can cause throttle body pressure problems. Safety wire the Fast Idle Cam open about halfway. It is added by factory for 2 main reasons. I dont have coolant running thru the TB and there is a reason for it. Posted by 10 months ago. and I have no idea what that … What It does: From the factory the throttle body has two coolant lines that run through it. I think you've got it backwards. I have no problem running too cool. well, cheap aluminum. The hose from the TB should dump into the upper portion of the radiator. They are less than a ft length each. Why does coolant go through the throttle body to begin with. There is always a reason behind the madness. Air is delivered to the engine through the throttle valve. You can also just leave the TB out of the loop. One is the inlet and the other one is the return. Having the coolant run through the TB helps so the TB does not freeze when it is very cold out. This thread is archived. If you remove your FIAV, your car will idle low when you first start it up. That's why it is bypassed in the summer and why it stops things from freezing in the winter. Archived. The hose on the pump can be capped off. Save Share. Bypass coolant system in summer to keep things cooler. Close. As I was unbolting my throttle body from my car to clean it, I heard a trickling sound. My engineer had done this to my throttle when I oversized the engine. Well first of all, what the coolant flowing through the throttle body does is operate the FIAV (fast idle air valve). TOM: What happens to them is that the throttle plate, the steel "flap" that lets The throttle body is a tube containing a pivoting flat valve (butterfly) that is used to control the amount of air entering an engine. F-Body cars (Camaro/Firebird) equipped with TPI motors have the exact same thing, a coolant inlet/outlet going through the throttle body, and it's listed as a "throttle body pre-heater," which simply, as stated above, serves to prevent the throttle body from freezing up … Z yaaaa- Coolant that has picked up heat through it's circuit is run around your throttle body, which heats it up and contributes to heat soak in the incoming air. It is one of the lines that goes to the throttle body and after I fixed it I was wondering why it needs to heat the trottle body. Advice on doing a throttle body coolant bypass The reason why they have hot water running through the throttle body is to warm it up more. share. This engine seems more temperature temperamental than any other car I have ever driven. After driving for awhile, your coolant will reach temperatures of up to 210F ...this hot coolant running through the throttle body heats up the air entering the engine and hurts performance. 62% Upvoted. A low coolant level may cause any of these components to misbehave. Top 7 Bad Throttle Body Symptoms. WTF gm; why run coolant through the throttle body? You crack the bleeder open and fill from the coolant resevoir until coolant flows out of the bleeder w/o air, then close it up. The hose which was attached to the top firewall coolant inlet on the TB should now be reattached at the hard-pipe, completing the rerouting. The whole idea is that the coolant of the engine does not pass through the throttle body, so even if the coolant becomes hot (when the engine gets worm), the throttle body remains cool, and so the throttle body sensor continues to keep the revs at a high level and generally the air-fuel ratio remains high. All modern vehicles run coolant through the throttle body, VW is no different. This is a component that acts as a gate-keeper and establishes a minimum or maximum position for a throttle body plate to be opened or closed. This can hurt your drag racing quarter mile times by as much as 3 tenths. There is no real difference between the temps of a bypassed one and a normal one. The coolant will reach nearly 200 degrees once the car is warmed up, and will transmit that heat through the throttle body … There is a slight chance of the throttle body iceing up. I would be afraid that in the winter here the car might run worse with … also, the ports combine to make a nice digital smilie. hide. Sure I'll post one tomorrow, but it should be the 2 hoses right under the throttle body. In a traditional spark ignition gasoline engine, the throttle body is the part of the air intake system that controls the amount of air that flows into an engine's combustion chamber. . The area underneath the TB was soaked but the leak didn't seem to be coming from the TB. IMPORTANT NOTE: If you live in extremely cold weather, this mod is not recommended. To do this the FIAV allows more air into the throttle body (TB) until the coolant temp reaches 122F. Small changes in temperature drastically changes the way the engine behaves. The coolant stops flowing when you shut the engine off, so there will no, repeat NO, effect on the rate at which the throttle body cools down. it's not anti-freeze. ... By the way, why are coolant hoses routed to the throttle body? The most common symptoms of a bad throttle body are check engine light, rough idle, high idle-RPM, rough acceleration, and poor engine performance.. I thought the TB had nothing to do with the cooling system, but obviously I was wrong. A vehicles coolant system is commonly employed to also help cool, throttle body’s, alternators, engine oil, turbo chargers and transmissions. 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