How to Bypass You TB Heater
- This part is actually available from your local parts store or Chevy dealer. It is an "L" shaped hose about 3" long. GM calls it a "Throttle body heater inlet hose" and the part number is 10115742. You need this "L" shaped hose because of the tight bend it must make. A straight hose would kink, cutting off the coolant flow. NOT a good thing! It is actually the stock hose use on some year's setups. You may be able to reuse the old hose, depending on your model year and the condition of the hose.
- 3/4" Hose Clamps. Available at any auto parts store
- Antifreeze - you are gona lose some:)
- Basic Tools
How To Do It
Undo the hose clamp and remove the intake tube from the throttle body. The picture below shows my custom intake, so your stock hose will look different. It will be black.
Remove the black vacuum hoses from the top of the throttle body. You can see them in the picture above, grouped in three. There are 2 bolts holding the throttle body on the plenum. Use a 13mm socket. You should remove these bolts to free up the TB from the plenum, so you can move it around to get the coolant lines off easier Why not Clean the Throttle Body right now?
Warning! Quite a bit of coolant will flow out of these lines once the hoses are removed. Be prepared and have something underneath the car to catch it, or you will have a big mess. You could also drain the coolant before hand if you like. Make sure you do this when the engine is cool, or you could get burnt by the coolant, and on the exhaust manifold. If the engine is cool, it will also minimize coolant loss.
The two lines you must remove are pictured below. To remove these hoses, undo the 4 hose clamps. The hose clamps may be the type that you unscrew a bolt on the clamp to loosen it, or you may have to squeeze two prongs together with pliers. Vice Grips work great for these kinds. The hoses will more than likely be stuck on pretty good, so you may have to cut them to get them off. The picture at right shows one of the hoses removed.
It may take a while, but eventually you will get both of them off. Once these lines are removed from the Throttle Body, it can easily be moved out of the way, giving you more room to work.
Now you need to attach your new hose to bypass the TB. The picture at right shows the 2 lines that are joined together with the new hose
Slide the two hose clamps over the hose, leaving them loose. Then secure the ends of the hose to the two coolant lines
Make sure the hose is on each end as far as it will go to ensure there are no leaks and tighten down the clamps.
You can just leave the heater attachment on the bottom of the throttle body. It wont hurt anything, and it is just a pain to remove unless you take the throttle body completely off, which involves the removal of the accelerator cables etc. It attaches with torx screws.
Re-install the 2 bolts that hold the TB to the plenum, then top off the coolant with approx. 70% antifreeze and 30% water.
Start up the car and check to make sure there are no leaks. If there are, make sure the clamps are tightened down securely. Take it for a drive. You probably won't be able to feel any sort of power gains from the mod, but take the car out for a drive anyway :)
If you put your hand on the TB or Plenum after the car has been running a while, you will notice it is much cooler than before. This is definitely a good thing! You now have a successfully bypassed throttle body heater!