Note On Intermittent
WARNING: This page is about a different car, the 1992 Cadillac Fleetwood and 1992 Cadillac DeVille. However, it is still accessible from the selected car via links, so may be relevant.
Check terminal crimp to wire and ensure terminals are properly seated in connectors.
5-volt reference can be tested by connecting jumpers between harness connector and MAP sensor terminal. Connect DVOM positive lead to jumper "C" and negative lead to jumper "A". Turn ignition on and apply vacuum to sensor. Tap lightly on sensor. Voltage reading should remain 4.6-5.1 volts.