P0402 on Ford
Exhaust Gas Recirculation Flow Excessive
P0402 on Ford vehicles indicates exhaust gas recirculation flow excessive. Au7o has documented this code across 4 Ford models — most commonly on Explorer, F-150, F-250 Super Duty. P0402 means the Exhaust Gas Recirculation (EGR) system is flowing too much exhaust back into the intake. The EGR system intentionally routes a small amount of inert exhaust gas into the engine to lower combustion temperatures and reduce nitrogen-oxide emissions, but the flow must be metered precisely. When the PCM determines the flow is excessive — often because the EGR valve is stuck open or letting gas through when it shouldn't — it sets this code. Too much EGR can cause rough idle, stalling, hesitation, and a check engine light. Typical repair costs on Ford range from $300 to $5,000, depending on the specific model and root cause.
Common Causes of P0402
- •EGR valve stuck open or not closing fully
- •Failed or sticking EGR valve diaphragm/solenoid
- •Carbon buildup holding the EGR valve open
- •Faulty EGR position or differential pressure (DPFE) sensor
- •Leaking EGR valve gasket or pintle seat
- •Vacuum control or solenoid fault commanding EGR open
- •Wiring or connector problems in the EGR control circuit
P0402 on Ford by Model
Ford Explorer(1 issue)
- 360-Degree / Rearview Camera System Failure2020-2024
A software failure in the 360-degree camera system's image processing module can cause the rearview camera to display a blank/black image when the vehicle is placed in reverse, or the image may remain frozen on the display after the backing event has ended. This affects driver visibility and increases the risk of backing collisions.
Ford F-150(1 issue)
- Driveshaft Carrier Bearing Failure2015-2020
The two-piece driveshaft uses a center support (carrier) bearing that can wear out, causing vibration and noise. The rubber support degrades over time, especially in hot climates or with heavy towing. Ford TSB addresses this issue.
Ford F-250 Super Duty(2 issues)
- 6.7L Power Stroke EGR Cooler Clogging and Failure2011-2019
The EGR (Exhaust Gas Recirculation) cooler on 2011-2019 6.7L Power Stroke diesel engines is prone to clogging with soot and eventually failing, particularly on trucks used for highway driving, light loads, or trucks that idle extensively. The EGR cooler recirculates cooled exhaust gas back into the intake to reduce NOx emissions. Over time, soot accumulates in the cooler's internal passages until coolant flow is restricted, causing the cooler to overheat and fail. When it fails, exhaust gases enter the coolant system, causing overheating and "puking" coolant from the degas bottle. The 2011-2014 models are particularly susceptible due to narrow internal coolant passages. Ford issued TSBs for 2011-2014 trucks covering EGR cooler cleaning/replacement under extended warranty up to 120,000 miles. The EGR cooler for 2011-2016 is OEM part BC3Z-9V425-A; 2017+ is HC3Z-9V425.
- 6.0L Powerstroke EGR Cooler Rupture and Coolant Leak2003-2007
The 6.0L Powerstroke diesel in 2003-2007 F-250s is infamous for EGR cooler failure. The cooler develops internal cracks that allow exhaust gas to enter the cooling system and coolant to enter the exhaust. This produces white smoke from the exhaust, coolant loss, and can cause hydrolocking if coolant enters the cylinders. The EGR cooler failure is often caused by clogged oil coolers that prevent proper coolant flow. This is arguably the most well-known diesel engine defect in Ford history.
Ford Maverick(1 issue)
- 12V Battery Drain and Loss of Drive Power - Recall 24S24 + SSM 530872022-2024
Ford Maverick trucks from 2022-2024 are affected by multiple 12V battery-related issues. Ford Safety Recall 24S24 (NHTSA 24V267) covers the BCM/PCM software inability to detect declining 12V battery performance, leading to Auto Start-Stop failures and vehicle stalling at low speeds. Additionally, Ford issued SSM (Special Service Message) 53087 for select 2022-2024 Maverick hybrids where the 12V battery drains intermittently when the ignition is turned off. MaverickTruckClub.com documents owners receiving "Remote Access disabled to reserve battery" FordPass alerts, with some needing 3+ battery replacements in 2-3 years. The hybrid system's complex 12V management appears to be the root cause of accelerated battery degradation.
Looking for P0402 on a different make?
View P0402 across all makes →Frequently Asked Questions
What does P0402 mean on Ford?▼
P0402 stands for "Exhaust Gas Recirculation Flow Excessive." P0402 means the Exhaust Gas Recirculation (EGR) system is flowing too much exhaust back into the intake. The EGR system intentionally routes a small amount of inert exhaust gas into the engine to lower combustion temperatures and reduce nitrogen-oxide emissions, but the flow must be metered precisely. When the PCM determines the flow is excessive — often because the EGR valve is stuck open or letting gas through when it shouldn't — it sets this code. Too much EGR can cause rough idle, stalling, hesitation, and a check engine light. On Ford specifically, this code is documented across 4 models.
What causes P0402 on Ford vehicles?▼
Common causes on Ford: EGR valve stuck open or not closing fully, Failed or sticking EGR valve diaphragm/solenoid, Carbon buildup holding the EGR valve open, Faulty EGR position or differential pressure (DPFE) sensor, Leaking EGR valve gasket or pintle seat. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0402 on a Ford?▼
Repair costs on Ford range from $300 to $5,000, depending on the specific model and root cause.
Which Ford models have P0402 documented?▼
Au7o has documented P0402 on 4 Ford models: Explorer, F-150, F-250 Super Duty, Maverick.