TPS Replacement

[roachd2]

On a 3800 series II the bottom screw on the TPS is immossible to remove. Do you have to take off the thermostat goose neck to remove it or is there is trick or special tool?

[BNaylor]

It is not impossible however GM used threadlocker on the TPS screws so it is not uncommon to have the screws break off. Unless you have the right 90 degree Torx allen wrench you'll probably have to remove the thermostat housing. Also, depending on the year the TPS screws may be the Torx tamper proof type so you will need a Torx T20 tamper proof bit.

[OJ_]

Originally Posted by roachd2

On a 3800 series II the bottom screw on the TPS is immossible to remove. Do you have to take off the thermostat goose neck to remove it or is there is trick or special tool?

Besides a tamper proof torx bit, nothing special is needed to remove the bolt.

You can use a wrench to turn the bit, it is kind of awkward but it beats spending time removing air bubbles from the coolant system due to removing the tstat elbow.

[BNaylor]

The TPS is a critical sensor so better to do the job right the first time. I would drain some coolant and remove the thermostat housing and it is no big deal topping off the coolant and doing an air bleed. The most compelling reason is it would be impossible to properly torque down the bottom TPS retaining screw which should be torqued with a torque wrench. 216 in-lb or 18 lb-ft per GM specs. Low to med strength threadlocker should always be used on the TPS screws. Those screws along with the IAC screws have a tendency to loosen up over a period of time if not secured properly.

[OJ_]

Originally Posted by BNaylor

The TPS is a critical sensor so better to do the job right the first time. I would drain some coolant and remove the thermostat housing and it is no big deal topping off the coolant and doing an air bleed. The most compelling reason is it would be impossible to properly torque down the bottom TPS retaining screw which should be torqued with a torque wrench. 216 in-lb or 18 lb-ft per GM specs. Low to med strength threadlocker should always be used on the TPS screws. Those screws along with the IAC screws have a tendency to loosen up over a period of time if not secured properly.

This man cannot lie, it would be ideal to follow his instructions.