Mazda Error Code P1405: How to Fix It

Q: What causes Mazda error code P1405?

P1405 is caused by the DPFE sensor's upstream vacuum hose being disconnected, cracked, or blocked with carbon deposits. This prevents the sensor from accurately measuring exhaust pressure differential.

Q: Can I drive with P1405 error code?

You can drive short distances, but avoid extended driving. P1405 can cause poor fuel economy, rough idling, and may prevent your vehicle from passing emissions tests. Address the issue promptly to avoid potential engine damage.

Q: How much does it cost to fix P1405?

DIY repairs typically cost $15-50 for replacement vacuum hoses. If the DPFE sensor needs replacement, add $50-150 for the part. Professional repair costs range from $150-400 depending on labor rates and parts needed.

Q: Will P1405 cause my Mazda to fail inspection?

Yes, P1405 will likely cause your vehicle to fail emissions testing since it affects the EGR system's operation. The error code must be resolved and the system must pass readiness tests before inspection.

Abstract

Error code P1405 in your Mazda indicates a problem with the DPFE (Differential Pressure Feedback EGR) sensor's upstream hose - it's either disconnected or blocked. This sensor monitors exhaust gas recirculation and when its hose is compromised, it can cause rough idling, poor fuel economy, and failed emissions tests.