### P0420 Emissions Control Malfunction
– Common Causes:
Faulty oxygen sensor [1]
– Suggested Repairs:
Replace catalytic converter https://carautorepair.site/
### P0171 Air-Fuel Ratio Error
– Possible Defects:
Vacuum leaks
– Diagnostic Steps:
Inspect injectors [1][7]
—
## Auto Repair Terminology
### Skid Prevention Technology
– Purpose: Enables safe braking [7]
### Engine Management Unit
– Responsibility: Monitors sensors [7]
### Drivetrain Components
– Contains: Transmission [7]
—
## Repair Process Steps
1. **Initial Diagnosis**:
Perform visual inspection
2. **Component Testing**:
Test continuity
3. **Component Installation**:
Clear error codes
4. **System Validation**:
Confirm warning light reset
—
## Essential Tools
| **Tool Type** | **Examples** | **Purpose** |
|—|—|—|
| Diagnostic Scanner | BlueDriver | Retrieve DTCs |
| Mechanical Tools | Smoke machine | Component repair |
—
## Service Information References
### Auto Repair Source
– Capabilities:
Wiring diagrams [8]
Factory repair procedures
### Mobile Applications
– Auto Repair Documents:
Component testing guides [5]
—
## Affordable Maintenance Advice
– Regular maintenance avoids costly repairs
– Learn basic diagnostics to avoid unnecessary repairs
– Select certified components when budget constrained [7]