Summary
The 1990 Buick Riviera has 6 recalls, the most serious involving the airbag system and the transmission shift cable: the driver's airbag inflator can separate during deployment, venting hot gases into the cabin instead of inflating the bag, and the shift cable can detach from the floor shifter, leaving the driver unable to tell what gear the transmission is actually in, which can cause unexpected vehicle movement.
On the restraint side, two recalls cover seatbelts. The rear shoulder belt retractor can stick in the locked position or fail to lock at all, either of which reduces protection in a hard stop or crash. A separate issue affects the front outer shoulder belt, where the web's sew stop can jam in the retractor and make the belt difficult or impossible to pull out and fasten. There is also a brake warning light issue: the indicator lamp may not illuminate when the ignition is on, the parking brake is applied, and the shifter is in park or neutral, meaning the driver loses a standard reminder that the parking brake is engaged.