Honda is extending warranty coverage on more than 1 million late-model Civics and CR-Vs due to an ongoing problem with gasoline dilution of crankcase oil in its 1.5L turbocharged 4-cyl.
Owners are being notified this month of a one-year warranty extension to six years and unlimited mileage (from 60,000 miles [96,600 k]) for “certain 2016-18 Civic and 2017-18 CR-V vehicles due to drivability concerns,” according to a bulletin issued by the automaker.
Honda spokesman Chris Martin says abnormal oil dilution remains “extremely rare, especially outside of extremely cold weather areas.” The problem occurs when unburned fuel slips past piston rings and mixes with engine oil in the crankcase.
“This warranty extension is primarily to provide reassurance to vehicle owners who may be concerned by varying oil levels in these engines, which, in most cases is normal and does not cause engine damage,” Martin says.
“In extreme and rare cases in the cold weather states, where abnormal oil dilution has occurred prior to a vehicle receiving the software updates, this extension will provide extra time for any undetected engine damage to become apparent and be covered by the warranty,” he says.
The 1.5L, part of the automaker’s highly efficient “Earth Dreams” family, is slow to reach optimum operating temperature that would normally cause fuel to readily evaporate and be routed back to the combustion chamber via the crankcase ventilation system.
Honda says short drives and extreme cold temperatures exacerbate the problem. Owners report oil levels above the “FULL” line on the dipstick and smelling gas in the cabin as well as in their garages after parking.
The extra warranty for vehicles in all 50 states specifically covers camshafts and rocker-arm assemblies and states the extension “addresses concerns related to engine oil dilution.”
The automaker says some vehicles may experience lack of power which may cause the “check engine” light to illuminate. Mechanics are instructed to listen for a “whirring noise from the engine” as part of diagnosing vehicles with camshaft damage.
Warranty extension covers more than 1 million vehicles.
The 50-state warranty extension follows bulletins issued by the Japanese automaker since last November requiring updates to nearly 400,000 Civics and CR-Vs sold in 21 cold-weather northern states.
Those updates, covering 143,000 ’16-’18 Civics and 239,000 ’17-’18 CR-Vs, are intended to help the engine warm up faster to prevent excessive gasoline dilution of engine oil. All ’19 models are being updated at the factory.
The repairs involve transmission and engine software changes that allow the engine to warm up quicker, reducing the possibility of unevaporated fuel collecting in the engine oil early in the drive cycle. Ignition timing, CVT control and air-conditioning operations are modified to help the engine warm up and retain heat.
Honda is addressing the problem with vehicles sold in China and Canada as well. A similar powertrain warranty extension was issued for Canadian owners last fall.
The 1.5L turbo 4-cyl. is standard on all but the base model CR-V and on upper-trim EX, EX-L and Touring models of the Civic. Wards Intelligence data shows 82% of the 766,000 ’17-’18 CR-Vs sold in the U.S. were equipped with the 1.5L, while about 47% of the 1.1 million ’16-’18 Civics came with the turbo powerplant.