How to Clean Throttle Body 88-98 GMC Sierra K1500

Difficulty: Intermediate · About 60 min · Gmc Sierra K1500

Clean the throttle body on a 1988–1998 GMC Sierra K1500, disconnecting sensors and cables carefully and protecting the throttle plate and bore.

Steps

1. Remove the air intake

   Release the air box latches and disconnect the intake temperature and airflow sensor plugs. Remove the breather line and intake fastener, then lift the intake hose away.

2. Remove the throttle body

   Disconnect the cruise and throttle cables and unplug the throttle position and idle air control sensors. Remove the cable bracket fastener and throttle body mounting bolts, then lift the throttle body off.

3. Clean the throttle body

   Use cleaner intended for throttle bodies and a soft brush to remove deposits from the bore and plate. Avoid soaking electrical components or damaging any protective coating, then wipe residue away.

4. Reinstall the throttle body

   Inspect the gasket and replace it if damaged. Seat the gasket and throttle body, install its fasteners to the vehicle's specification, and reconnect the cable bracket, cables, and sensor plugs.

5. Restore the intake and verify

   Reconnect the intake hose, breather line, and sensor plugs, then secure the air box cover and clamps. Start the engine and check for leaks, warning lights, or an unstable idle.

Check your vehicle’s repair manual for exact specifications and fit.