Where is the throttle valve adjuster on a grand prix gt?

There isn't a throttle valve adjuster in the traditional sense on a Pontiac Grand Prix GT (or most modern fuel-injected vehicles). The throttle position is controlled electronically by the throttle body and the engine control module (ECM). There's no manually adjustable screw or cable.

Any adjustments to the throttle response would be done through:

* ECM Calibration/Programming: This is done with specialized diagnostic tools and software. It's how professionals might adjust throttle sensitivity or compensate for modifications.

* Throttle Body Cleaning: A dirty throttle body can affect response. Cleaning it can improve throttle performance. However, this is cleaning, not adjusting.

* Throttle Position Sensor (TPS) Replacement: A faulty TPS will cause problems. Replacing it is a repair, not an adjustment.

If you're having throttle issues, don't try to manually adjust anything. Take it to a qualified mechanic for diagnosis and repair. Attempting to adjust something that isn't meant to be adjusted can damage the vehicle's computer system.