There are 1 owner-reported engine complaints for the 2018 Toyota Prius Primein NHTSA's database. These are unverified consumer reports and may not reflect confirmed defects.
AFTER THE HYBRID BATTERY IS DISCHARGED, AND THE GAS ENGINE KICKS IN, THE VEHICLE LOSES POWER FOR APPROXIMATELY 5-10 SECONDS ON THE FREEWAY. THIS HAS HAPPENED FOUR TIMES, AT APPROXIMATELY 7 AM, ON DECEMBER 1, 10, 14 AND 15. ON ALL OCCASIONS, THE TEMPERATURE WAS BETWEEN 40-45 DEGREES FAHRENHEIT, AND AT HIGHWAY SPEEDS. THE CRUISE CONTROL WAS NOT IN USE. NO WARNING LIGHTS CAME ON. I CALLED THE TOYOTA DEALER ON DECEMBER 1 AND THE SERVICE ADVISER SAID THAT SINCE NO WARNING LIGHTS CAME ON, HE COULD NOT DETERMINE THE PROBLEM. I HAVE A PHOTO SHOWING MY CONTACTING THE TOYOTA DEALER ON DECEMBER 1ST. ON DECEMBER 10, I TOOK THE VEHICLE INTO TOYOTA IN THE AFTERNOON. THE DEALER CHECKED THE VEHICLE AND ROAD TESTED THE VEHICLE WITHOUT HAVING THE HYBRID BATTERY CHARGED, AND THE AIR TEMPERATURE WAS WARMER. I WAS CHARGED $210 FOR THE DIAGNOSTIC SERVICE, ALTHOUGH I HAVE AN EXTENDED WARRANTY. THE SAME PROBLEM OCCURRED ON DECEMBER 14 AND 15. SPECIFIC PROBLEM UNKNOWN BUT I BELIEVE THAT A SWITCH THAT CONTROLS THE GASOLINE VOLUME INTO THE ENGINE AFTER THE HYBRID BATTERY POWER IS DEPLETED IS DEFECTIVE. I WAS IN THE CARPOOL LANE AT APPROXIMATELY 7 AM ON ALL 4 OCCASIONS AND MY SPEED DROPPED, ALTHOUGH I DEPRESSED THE GAS PEDAL TO MAXIMUM AS WELL AS PUMPING THE GAS PEDAL, ALL TO NO AVAIL. THE CAR IS IN USE ONLY MONDAY, TUESDAY, WEDNESDAY AND THURSDAY, THE DAYS THAT I WORK. I CONTACTED TOYOTA CUSTOMER ADVOCATE (800-331-4331, CASE # 2012120505) AND THEY SAID THEY DID NOT HAVE THE ABILITY TO DETERMINE IF ANYONE ELSE EVER HAD THE SAME PROBLEM.
Complaints are unverified consumer reports submitted to NHTSA. A high complaint count may reflect vehicle popularity, not defect severity. Data sourced from NHTSA public records.
Data synced from NHTSA on Apr 26, 2026