P1128 Buick Throttle Control Motor Circuit Short

P1129 Buick Manifold Absolute Pressure Sensor Circuit Higher Than Expected

Possible causes
– Faulty Manifold Absolute Pressure Sensor
– Manifold Absolute Pressure Sensor harness is open or shorted
– Manifold Absolute Pressure Sensor circuit poor electrical connection
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)
– Engine hard to start
– Rough or erratic idle speed
P1129 Buick Description

The Manifold