P0404 on Volkswagen: How to Diagnose & Fix
Exhaust Gas Recirculation Circuit Range/Performance
1 Volkswagen model · 1 documented issue · $350-$1,500 repair
P0404 on Volkswagen by model: symptoms, diagnosis and fix
The EA189-family TDI diesels (1.6 and 2.0 TDI) suffer frequent EGR valve failures from carbon/soot build-up that jams the valve. The problem became markedly worse after the Dieselgate emissions software fix, which makes the EGR system work harder and has been widely linked to premature EGR failures. Owners report the valve jamming and the engine going into limp mode, with several quoted around £1,400-£1,500 for replacement. Volkswagen has, in many cases, refunded owners for EGR failures occurring after the emissions update.
Common Symptoms
- Engine management / check engine light on
- Loss of power and limp mode
- Rough idle and hesitation
- Increased exhaust smoke
- Higher fuel consumption
How to Fix
Clean or replace the EGR valve (and EGR cooler if clogged). Where failure followed the emissions fix, owners should pursue VW/the supplying dealer for a free-of-charge repair or refund, as VW has refunded many such claims. Regular longer-run driving and a quality EGR-cleaning service slow re-fouling.
Sources for this issue (2)
P0404 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P0404 mean on a Volkswagen?
P0404 stands for "Exhaust Gas Recirculation Circuit Range/Performance." This code means the exhaust gas recirculation (EGR) system isn't performing within its expected range. The EGR valve routes a metered amount of exhaust gas back into the intake to lower combustion temperatures and reduce nitrogen-oxide emissions, and the computer monitors the valve's actual position versus what it commanded. When the valve sticks, moves incorrectly, or the feedback doesn't match the command, P0404 sets. This can cause rough idle, hesitation, pinging, and increased emissions. On Volkswagen it is documented across 1 model: Touran.
What are the most common causes of P0404?
The most common causes of P0404 are: Carbon buildup clogging the EGR valve or passages, Sticking or failed EGR valve, Faulty EGR position sensor, Corroded or loose EGR connector, Damaged or shorted EGR wiring, Vacuum leak or failed vacuum control (on vacuum-operated systems), Clogged EGR cooler or tubes, Faulty PCM/ECM (rare). The specific cause varies by vehicle.
How much does it cost to fix P0404 on a Volkswagen?
Published repair estimates on Volkswagen range from $350 to $1,500 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for P0404 on a different make?
View P0404 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.