How To Service a LS1 Throttle Body

How To Service a LS1 Throttle Body


There’s a lot of reasons why you would want to remove your LS1 throttle body that can be both maintenance or performance orientated. Consider a free modification like grinding your LS1 bump stop for 100% wide open throttle, or adjusting your idle screw.

Today I’ll be showing you how to service a LS1 throttle body, how to remove it and how to clean and service each one of the sensors.

There are many check engine codes that can also require you to remove your throttle body. This can also cover the throttle body gasket or if you need to replace your throttle body which is GM part number 17113390 for a 1998-99 LS1, 17113564 for 1998-99, 17113647 for the 2000-01 and 17113669 for the LS6.

Before you begin our tutorial on how to service a LS1 throttle body, disconnect the negative terminal on your battery.

Unplug your MAF connector and the air intake temperature sensor and detach your intake snorkel and airbox if applicable.


Using your hand, depress on the throttle body blade and slowly open the throttle body.


When you have the throttle body completely open, slide out the throttle cable end from the slot in your throttle butterfly.


In this position turn the throttle cable and pull the end out of your throttle body.

Disconnect the throttle body position sensor and all the vacuum lines. If you have not already bypassed your coolant lines, do this now and allow the coolant to bleed out. Have a rag handy to soak up the small amount of coolant that may leak out.

Unbolt the throttle body by undoing the three 10mm bolts on the top and the bottom corners.


Once your LS1 throttle body is removed you should clean the back of the throttle body to clear it from carbon and any buildup. Check the orange rubber throttle body gasket for any damage or pinching which could lead to an intake leak.


This is the LS1 base idle screw which can adjust the closed position for your throttle body. If you are in need of adjusting this screw, you will require a T15H sized star key to adjust this.

Testing your LS1 throttle position sensor involves the use of a multimeter. If you are not familiar with what a multimeter or voltmeter does, please check our How To Article here.

The LS1 TPS connector is a three pin unit that is triangular in shape. It’s also usually the longest wire connector in your wiring harness if you are working on a LS1 swap. Check here for our How Tos on swapping a LS1 in a 240SX, a Miata as well as How To Wire a LS1 into a S14 and S13.

How To Service your LS1 TPS

Replacing your LS1 throttle position sensor is easy and straightforward and does not require you to remove your throttle body. For our How To on how to replace your LS1 throttle position sensor (TPS) check this link.


This might also be a good time to look into upgrading your intake manifold to a LS6 unit, which is also very easy and that How To is here.

When reinstalling your throttle body, make sure to check your throttle body gasket and ensure that it is intact. Torque to specification and then reconnect your intake snorkel and all of your intake related electrical sensors. That does it for our how to service a LS1 throttle body article, if you have any questions please feel free to leave them below!