---
title: "2018 Honda Accord Engine Problems: What Owners Report"
description: "2018 Accord engines fail at 45k+ miles. Head gasket failure, oil dilution, and AC problems are common. Learn what to watch for."
canonical: "https://sidekick.vin/answers/what-are-common-problems-with-2018-honda-accord-engines-around-120000-miles"
type: "qa"
vertical: "maintenance"
lastModified: "2026-02-26T13:24:00.779Z"
keywords: ["2018 Honda Accord engine problems", "head gasket failure 2018 Accord", "1.5T engine issues", "Honda Accord reliability 100k miles"]
---
# What are common problems with 2018 Honda Accord engines around 120,000 miles?

> **Quick Answer:** The 2018 Honda Accord's 1.5T engine has documented head gasket failures starting at 45,000 miles, even on well-maintained cars. Oil dilution and air conditioning problems are also common.

**Category:** maintenance
**Question Type:** troubleshooting

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---
# Common 2018 Honda Accord Engine Problems

The 2018 Honda Accord's 1.5T engine develops serious issues well before 120,000 miles. The most critical problem is **head gasket failure**, which owners report happening as early as 45,000 miles on stock, unmodified vehicles.

## Head Gasket Failures

This is the biggest concern for 2018 Accord owners. Even cars with perfect maintenance records experience blown head gaskets. Warning signs include:

- Overheating
- Misfiring
- Loss of power
- Low coolant levels
- Check engine light that triggers limp mode (limiting you to 10 mph)

When the check engine light comes on for a head gasket issue, the car enters limp mode immediately. This safety feature prevents you from driving normally, making it a critical failure rather than a gradual decline.

One owner with a well-maintained 2018 Accord needed a complete engine replacement at 90,000 miles due to a blown head gasket. Honda corporate refused to cover the repair despite documented 5,000-mile oil changes and perfect maintenance.

## Oil Dilution in 1.5T Engines

The 1.5T engine also suffers from **oil dilution problems**, especially in earlier model years. Some owners report the engine consuming about one quart of oil every 1,000 miles. This accelerates engine wear and increases failure risk.

## Air Conditioning Issues

The 2018 Accord frequently experiences air conditioning failures. Common issues include:

- AC compressor failure
- Condenser leaks
- Refrigerant loss
- Coolant leakage

Many owners report the new coolant required in these Hondas loses fluid more easily than traditional options. Some dealers have extended warranties to cover AC repairs even after the factory warranty expires.

## Other Engine Concerns

Button sticking on the dashboard is also common on these vehicles, though it's less serious than engine problems.

## What This Means for Buyers

If you're considering a used 2018 Accord, the 1.5T turbo engine carries significant risk. Many experts recommend choosing the naturally aspirated 2.0L engine instead. If you do buy a 1.5T model, get a pre-purchase inspection and budget for potential major repairs.

Using high-grade fuel won't solve the oil dilution problems. Some owners report that GF-6 engine oil may help, but this won't prevent head gasket failures.

Tracking your maintenance history is essential. Keep records of all oil changes, service dates, and any engine warning signs. This documentation helps if you need to file complaints or pursue warranty claims with Honda.