Honda Error Code P1129: How to Fix It

Q: What causes Honda P1129 error code?

P1129 is typically caused by a damaged MAP sensor vacuum hose, faulty MAP sensor, vacuum leaks in the intake system, or poor electrical connections to the MAP sensor.

Q: Can I drive my Honda with P1129 code?

While you can drive short distances, P1129 can cause poor fuel economy, rough idling, and reduced performance. It should be diagnosed and repaired promptly to prevent potential engine damage.

Q: How much does it cost to fix P1129 on a Honda?

Repair costs vary from $20-50 for a vacuum hose replacement to $150-300 for MAP sensor replacement at a shop. DIY repairs using quality parts typically cost $30-150 depending on what needs replacement.

Q: Will P1129 cause my Honda to fail emissions test?

Yes, P1129 will likely cause your vehicle to fail emissions testing as it affects the air-fuel mixture. The code must be resolved and the readiness monitors must complete before passing inspection.

Q: How do I know if my MAP sensor is bad?

A bad MAP sensor typically shows symptoms like rough idle, poor acceleration, black exhaust smoke, or stalling. Testing with a multimeter will show voltage readings outside the normal 1-5 volt range during engine operation.

Abstract

Honda error code P1129 indicates that the Manifold Absolute Pressure (MAP) sensor is reading higher pressure values than expected by the ECU. This can cause poor engine performance, rough idling, and reduced fuel economy.