2018 Honda CR-V Oil Dilution Inspection Guide

The 2018 Honda CR-V with the 1.5L turbocharged engine (L15B7) has a known oil dilution issue that made national news when it was first reported. If you own one of these vehicles, you need to understand what oil dilution is, what Honda's TSB says, and how to properly check your oil level and condition.

What Is Oil Dilution?

Oil dilution happens when gasoline mixes with engine oil. In turbocharged direct-injection engines, unburned fuel can wash past the piston rings during cold starts and short-trip driving — especially in cold weather — and enter the crankcase. This thins the oil and reduces its ability to lubricate engine components.

Signs of oil dilution in the 2018 Honda CR-V 1.5T:

• Oil level reads higher than normal on the dipstick
• Noticeable gasoline smell when you remove the oil filler cap
• Thinner-than-normal oil appearance on the dipstick

Honda TSB 19-087

Honda issued TSB 19-087 addressing the 2017–2019 CR-V 1.5T oil dilution issue. The TSB acknowledges the L15B7 engine can experience fuel in the oil under cold-climate, short-trip conditions. Honda's remedy includes an ECU software update that adjusts fuel injection parameters. The update reduces frequency but does not eliminate the underlying mechanical cause.

Correct Oil Level Check Procedure (TSB Method)

Cold soak check (best for detecting dilution):

1. Leave car parked overnight — minimum 8 hours
2. Before starting, pull the dipstick and check level
3. If above the F mark, that's a red flag for dilution
4. Smell the dipstick — strong gasoline smell = oil dilution

After full warm-up (accurate volume reading):

1. Drive at highway speeds for 20–30 minutes
2. Park level, shut off, wait 5 minutes
3. Check dipstick — still above F after highway drive = significant dilution

What to Do If You Find Oil Dilution

1. Get the ECU update — Request TSB 19-087 at a Honda dealer. Free on affected VINs.
2. Change the oil immediately — Diluted oil provides inadequate lubrication.
3. Change driving habits — Consolidate short trips; highway driving evaporates diluted fuel.
4. Document everything — If within 5-year/60,000-mile powertrain warranty, document each event.

Oil spec for the 2018 CR-V 1.5T:

• 0W-20 full-synthetic (API SN+ or SP)
• Capacity: 3.4 quarts (3.2L) with filter
• Honda part number: 08798-9036 (1 quart)

Do not use a heavier grade to compensate for dilution — it doesn't fix the problem and adds cold-start wear.

Final Thoughts

The 2018 Honda CR-V is otherwise an excellent crossover. The 1.5T oil dilution issue is manageable with awareness and proper maintenance. Get the ECU update, check oil regularly, and change it on shorter intervals in winter. For more Honda-specific DIY guides, see all guides at /blog or access everything with an OwnerDrop Starter subscription at $29.99/mo.