2018 Toyota Sienna Reliability Report

Third-row power seats that fold on their own are the most serious hazard here. The seats close on a buckled passenger at highway speed, and then the buttons stop working for several minutes. One van stalled at 20 mph with the master warning light on. That stall is tied to the fuel pump recall, and parts were not available at the time. Other reports cover a dead Safety Connect SOS system that dealer resets did not fix and a tire pressure warning light that stays on. In one case, a dealer sold a van listed at 57,000 miles whose registration showed 175,152.

Front air bags failing to deploy in serious crashes is the pattern. Reports describe frontal impacts at 60 and 74 mph. In a 70 mph rear-end collision that ended in a rollover, the side air bags fired but the front ones did not. Injuries include bruised ribs, a bruised lung, a concussion, and a sore shoulder. In a separate crash where every air bag deployed, interior light covers broke loose and scratched a passenger. All 4 complaints involve crashes, with 5 people injured.

Power sliding doors cause most of the trouble. A broken door cable leaves the door unable to open. One report says a closing door did not stop for an obstruction. It caught an adult's arm and nearly trapped a child. Front bumper clips pop loose from airflow at speed and tear the plastic support frame, and the dealer quoted a full bumper replacement. A loose driver-side carpet near the pedals also touched the driver's foot at 4,700 miles and was not repaired.

Waiting on parts for the fuel pump recall drives most of these reports. Dealers repeatedly confirmed the remedy parts were unavailable, and owners felt the delay ran too long. Two reports describe real symptoms. In one, the van did not respond to the accelerator at 70 mph with no warning light, and the problem returned after the recall repair. In the other, the van surged forward at idle with a warning light on. Loss of power at highway speed is the main safety risk.

Sudden loss of power and stalling make up the more serious report. The van jerks, loses motive power, and shuts off on its own. The dealer could not reproduce the fault, and it continued even after the fuel pump was replaced under a recall. The other complaint involves the oil warning light coming on during a low-speed turn. The oil level was low and dropped again after the dealer topped it up, first at 3,700 miles. A stall in traffic carries a loss-of-control risk.

Unintended full-throttle acceleration in reverse, while backing out of a driveway, led to the one crash-related report. The other describes a torque converter clutch pressure control solenoid circuit fault that appeared once the van reached speed. The owner says a friend's van of the same model had the same issue. With only 2 complaints there is no clear pattern, but the surge in reverse is a serious loss-of-control event.

Rear seats that shift or move on their own are the concern. In one report all four rear seats slid forward by themselves while the van sat still, starting at 1,000 miles. Two dealer repairs to the floor rail caps did not stop it. Another describes third-row seat latches that rotate and let the seats twist and slide. Two dealers called this normal play. These seats anchor child seats and seat belts, so owners worry about how they would hold in a crash.