P0402 on RAM
Exhaust Gas Recirculation Flow Excessive
P0402 on RAM vehicles indicates exhaust gas recirculation flow excessive. Au7o has documented this code across 2 RAM models — most commonly on 1500, ProMaster. 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 RAM range from $40 to $2,500, 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 RAM by Model
RAM 1500(1 issue)
- Dashboard Cracking and Warping2019-2024
The 2019-2024 RAM 1500 dashboard develops cracks, warping, and deformation, particularly in hot climates. Cracks commonly appear near the defroster vents, along the passenger side airbag seam, and around the center console area. The issue is attributed to UV exposure and thermal cycling degrading the dashboard material. Vehicles parked outdoors in southern states (AZ, TX, NV, FL) are most affected. While primarily cosmetic, cracks near the passenger airbag seam could theoretically affect airbag deployment. Dashboard replacement costs $1,500-2,500+ at the dealer.
RAM ProMaster(1 issue)
- 3.6L Pentastar V6 Oil Filter Housing/Cooler Leak2014-2025
The RAM ProMaster with the 3.6L Pentastar V6 engine suffers from a well-known oil filter housing/cooler leak. The oil filter housing is mounted to the side of the engine block and contains an integrated oil cooler. The gaskets and O-rings that seal the housing deteriorate over time, causing oil to leak externally (visible drip on the ground) and/or internally (oil mixing with coolant). If oil enters the cooling system, it destroys the coolant and can cause overheating. The leak typically appears between 40,000-80,000 miles. This is the same issue that affects all Pentastar 3.6L vehicles (Jeep, Dodge, Chrysler). Mopar updated the housing design (68105583AF) with improved seals.
Looking for P0402 on a different make?
View P0402 across all makes →Frequently Asked Questions
What does P0402 mean on RAM?▼
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 RAM specifically, this code is documented across 2 models.
What causes P0402 on RAM vehicles?▼
Common causes on RAM: 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 RAM?▼
Repair costs on RAM range from $40 to $2,500, depending on the specific model and root cause.
Which RAM models have P0402 documented?▼
Au7o has documented P0402 on 2 RAM models: 1500, ProMaster.