2018 Buick Enclave: What to check before buying

The electronic parking brake sets itself while driving or stopped at lights. Sometimes it refuses to release, which strands cars in intersections and leads to tows. In another pattern, the pedal stops slowing the car and a brake assist or service brake warning appears, often after a cold start or while backing up. Two reports involve crashes. Other complaints describe ABS faults, including a module that needed reprogramming near 52,000 miles, and loud grinding near 60,000. Repeat dealer visits often fail to fix the problem.

The transmission stops working. Cars will not shift into Drive or Reverse, stall in traffic, or grind when the driver presses the gas, and some needed a new transmission at about 71,000 or 110,000 miles. A second pattern is hard shaking under acceleration, which mechanics blame on the torque converter. In at least one case it continued after the transmission was replaced. Some cars drop into neutral after auto stop, especially after refueling. Dealers often find no fault or blame programming. One report involves a crash.

Parking brake faults show up here too. The brake fails to release fully, drags hard enough to leave a rear brake hot, or will not engage at all. In one case a loose wire rubbed against the rear CV boot, shorted out, and damaged the ABS module. Auto stop can shut down the whole car while it is in Drive, followed by Service Transmission and Service Parking Brake messages. One driver reports a total power loss in highway traffic. Isolated reports mention flickering headlights, an airbag light, and locks cycling on their own.

Auto stop-start draws most of these complaints. The engine shuts off at a stop and then hesitates or ignores the gas pedal when the driver tries to pull away into traffic. Dealers say the feature works as built and has no fix, and drivers cannot turn it off. One car bucked, would not accelerate, and rolled backward with cam timing codes such as P0011 stored. Another report describes a broken front exhaust pipe that caused loud roaring, lower fuel economy, and worry about carbon monoxide.

Power steering cuts out as the engine restarts after auto stop, so the wheel turns hard just as the driver pulls away or turns. In that report the car also shuts off at random, and the problem began around 60,000 miles. A separate complaint describes shaking, an engine warning, and power loss on a busy road. The oil level was low each time, and adding oil cleared the lights for a while. Both patterns create a loss-of-control risk in traffic.

Fuel vapor leaks. One car less than a year old gives off a strong gasoline smell, bad enough that the owner keeps it out of the attached garage. Another report traces a check engine light and code P0496 to an EVAP purge solenoid that does not seal, which a dealer repaired. Neither report mentions a fire.

The sunroof glass shatters suddenly while the car is moving, with a bang loud enough to sound like a gunshot. Both reports involve normal driving with no impact: one during a slow left turn at about 15 mph, the other on a highway with no overpass nearby. In one case the closed shade kept glass from falling into the cabin. In the other, the panel was left with a large hole.