Engine problems in Hondas are rare, but the Japanese automaker is dealing with an over-fueling glitch in its top-selling vehicle in the U.S., the CR-V compact crossover.
The problem affects CR-Vs with 1.5-liter engines driven on short trips in cold weather. Under those conditions, a number of the engines' crankcases have filled with gasoline. The problem has occurred in several markets, including China.
Honda spokesman Chris Martin said a fix for U.S. vehicles is expected to be ready next month. He would not provide technical details on what causes the problem or say how Honda plans to fix it. In China, where the same engine is used but with different tuning, and on versions of the CR-V with different equipment, Honda engineers fixed the problem with a software patch, Martin said.
Consumer Reports, in a report Friday, says nine of its members who own CR-Vs and dozens of other CR-V owners have reported the problem.
The magazine said dozens of other CR-V owners have complained about similar experiences to the National Highway Traffic Safety Administration.
When engines are cold, the fuel injection system shoots a richer mixture of fuel into each cylinder. As the engine warms, the fuel-to-air mixture becomes leaner. But if the engine is shut off before it reaches operating temperature, it will continually run rich. Some CR-V owners have said their vehicles have lost power and stalled, a problem that appears related to the over-fueling problem.
The CR-V's 1.5-liter engine has direct fuel injection, which sprays fuel directly into each of the four cylinders. If too much gasoline is injected into the engine, some would get past the piston's rings and drip into the crankcase. Some CR-V owners have been able to temporarily solve the problem by having their oil drained and changed.
Honda says the problem has surfaced in 2017 and 2018 CR-Vs. "At this time, Honda has no reason to believe that this issue affects the safe operation of a vehicle or results in any U.S. regulatory non-compliance," the company said in a statement.
Martin says Honda didn't simply try to use the same repair on U.S. vehicles as it did in China because the company wanted to investigate the problems on vehicles calibrated for North America.
"There are differences between vehicles and engines sold in various markets around the world, and it is prudent and appropriate to take time to properly investigate how seemingly similar symptoms may affect those different configurations and to identify the best strategy for addressing them in each particular market," Honda said. "Vehicles are more complex than other consumer goods, like mobile phones, etc., and any changes must be carefully considered in light of vehicle differences, localized consumer preferences and their potential impact on vehicle regulations in that market."