### P0420 Catalyst System Efficiency Below Threshold
– Frequent Reasons:
Worn catalytic converter [1]
– Common Solutions:
Repair exhaust system https://carautorepair.site/
### P0171 Air-Fuel Ratio Error
– Likely Problems:
Vacuum leaks
– Diagnostic Steps:
Smoke test intake [1][7]
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## Vehicle Service Vocabulary
### ABS (Anti-Lock Brake System)
– Purpose: Enables safe braking [7]
### Engine Management Unit
– Responsibility: Controls ignition timing [7]
### Powertrain Elements
– Contains: Transmission [7]
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## Mechanical Fixing Workflow
1. **Initial Diagnosis**:
Conduct road test
2. **Part Evaluation**:
Measure resistance
3. **Parts Replacement**:
Clear error codes
4. **Final Quality Check**:
Confirm warning light reset
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## Essential Tools
| **Tool Type** | **Examples** | **Purpose** |
|—|—|—|
| Diagnostic Scanner | Innova | Retrieve DTCs |
| Hand Instruments | Smoke machine | Electrical testing |
—
## Technical Data Resources
### Vehicle Service Database
– Features:
Wiring diagrams [8]
OEM specifications
### Digital Assistants
– Auto Repair Documents:
ECU pinouts [5]
—
## Affordable Maintenance Advice
– Preventative service avoids costly repairs
– Learn basic diagnostics to avoid unnecessary repairs
– Select certified components when budget constrained [7]