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P0304 on FORD FUSION

Severity
Medium
NHTSA Reports
17
Most Affected
2016, 2015, 2017

What P0304 Means on Your FORD FUSION

Real FORD FUSION Owner Reports (Source: NHTSA Complaints Database)

"Coolant leak from freeze out plug causing car to overheat first engine light flashed causing a p0304 code then smelled coolant and started overheating"

— 2013 FORD FUSION owner • ENGINE • Filed 03/09/2020

"My Ford fusion has a coolant leak and ford said I need a repair. Price for repair is $9,584.89. It is a known problem with a TSB (see below) Summary This article supersedes TSB 19-2139 to update the production fix date."

— 2015 FORD FUSION owner • UNKNOWN OR OTHER • Filed 12/14/2022

"2015 1.5L Ecoboost misfiring/running rough/coolant level low. While driving highway speeds engine began to lose power and shutter ultimately shutting down causing significant lose of braking and steering."

— 2015 FORD FUSION owner • ENGINE • Filed 04/01/2022

"Just got this ford vehicle a couple months ago and for some reason my car wouldn't start. i ran a diagnostic and had numerous codes p0300, p0301, p0302, p0303, p0304, p0030, c0014, p0047, p0141, and a few others. i looked for loose wires, checked fuses, plugs etc."

— 2015 FORD FUSION owner • ENGINE • Filed 03/17/2021

"Coolant intrusion into cylinder 1, low coolant and Engine DTC P0301. Multiple TSB's by Ford recommend engine replacement as a remedy for the Cylinder head - open deck cooling problem. Customer Satisfaction Program 21N12 addresses this problem in similar cars/engines."

— 2016 FORD FUSION owner • ENGINE • Filed 06/01/2025

Data from NHTSA Vehicle Complaints Database. All reports are filed by vehicle owners directly with the U.S. Department of Transportation.

Common Causes of P0304 on FORD FUSION

64.7%
11.8%
5.9%
5.9%
5.9%

Percentages based on NHTSA complaint component analysis for this vehicle.

Complaint Trend by Year

2013
1
2015
3
2016
6
2017
3
2018
1
2019
3

What To Do Next

  1. 1
    Check for recalls on YOUR VIN

    Go to nhtsa.gov/recalls and enter your VIN. Free repairs if your vehicle is covered.

  2. 2
    Get a proper diagnosis

    A code alone doesn't tell you the exact failed part. A diagnostic at a shop ($50-$150) pinpoints the root cause before you spend money on parts.

  3. 3
    Compare repair quotes

    Get 2-3 quotes. Dealer vs independent shop prices often differ 30-50% for the same repair.

P0304 on Other Vehicles

Data sourced from the National Highway Traffic Safety Administration (U.S. Department of Transportation) and the SAE J2012 OBD-II standard. Code definitions follow the SAE J2012 / ISO 15031-6 standard. Owner reports are filed directly with NHTSA by vehicle owners. This information is provided for educational purposes only and should not replace professional automotive diagnosis. Always consult a qualified mechanic for vehicle repair decisions.

Last updated: March 2026