O2 Sensor Circuit Slow Response (Bank 1 Sensor 1)
The DURAMAX-P0133 (Duramax) diesel fault code means: O2 Sensor Circuit Slow Response (Bank 1 Sensor 1). This is a moderate severity code.
- Keep driving?
- Yes, with caution
- DIY difficulty
- intermediate
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What Are the Symptoms of DURAMAX-P0133?
- Check Engine Light on
- Usually no change in how the truck drives
What Causes DURAMAX-P0133? (Most Likely First)
- Aging or contaminated oxygen sensor High
- Exhaust leak near the sensor Moderate
- Wiring or connector damage Low
Can I Still Drive with DURAMAX-P0133?
Yes, with caution. DURAMAX-P0133 is rated moderate severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.
Frequently Asked Questions
What does P0133 mean on a Duramax?
P0133 means O2 Sensor Circuit Slow Response (Bank 1 Sensor 1). The bank 1 sensor 1 oxygen sensor is responding more slowly than expected to changes in the exhaust.
Is P0133 a Duramax-specific code?
No. P0133 is a generic OBD-II code defined by SAE J2012, so it means the same thing on any vehicle that sets it. The exact conditions GM uses to set it on its diesels are in GM service information.
Mechanics Guide Step-by-step diagnosis
How Do You Diagnose DURAMAX-P0133?
Check for exhaust leaks near the sensor.
Watch the sensor reading on a scan tool as conditions change.
Inspect the sensor wiring for heat damage.
Sources 1
This page is built from documented references. Verify against your own service info before repair work.
- SAE J2012Diagnostic Trouble Code Definitions (defines P0133 as a generic OBD-II code)
P0133 on Other Platforms
The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown:
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