### P0420 Catalyst System Efficiency Below Threshold
– Typical Sources:
Faulty oxygen sensor [1]
– Recommended Fixes:
Diagnose fuel trim https://carautorepair.site/
### P0171 Fuel Mixture Imbalance
– Likely Problems:
Fuel delivery problems
– Diagnostic Steps:
Check fuel pressure [1][7]
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## Auto Repair Terminology
### Electronic Braking System
– Purpose: Prevents wheel lockup [7]
### ECM/ECU (Engine Control Module)
– Responsibility: Controls ignition timing [7]
### Powertrain Elements
– Contains: Drive axles [7]
—
## Mechanical Fixing Workflow
1. **Problem Identification**:
Conduct road test
2. **Part Evaluation**:
Test continuity
3. **Parts Replacement**:
Use OEM parts
4. **System Validation**:
Confirm warning light reset
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## Necessary Equipment
| **Tool Type** | **Examples** | **Purpose** |
|—|—|—|
| Code Reader | Autel | Live data streaming |
| Physical Equipment | Smoke machine | Component repair |
—
## Technical Data Resources
### Vehicle Service Database
– Features:
Wiring diagrams [8]
Technical illustrations
### Digital Assistants
– Auto Repair Documents:
Component testing guides [5]
—
## Budget Repair Strategies
– Routine checkups avoids costly repairs
– Learn basic diagnostics to avoid unnecessary repairs
– Use aftermarket parts when OEM prices prohibitive [7]
