### P0420 Catalyst System Efficiency Below Threshold
– Frequent Reasons:
Exhaust leaks [1]
– Common Solutions:
Diagnose fuel trim https://carautorepair.site/
### P0171 Fuel Mixture Imbalance
– Possible Defects:
Fuel delivery problems
– Testing Procedure:
Check fuel pressure [1][7]
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## Vehicle Service Vocabulary
### ABS (Anti-Lock Brake System)
– Purpose: Enables safe braking [7]
### Vehicle Computer System
– Responsibility: Manages fuel injection [7]
### Transmission System Parts
– Includes: Differential [7]
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## Mechanical Fixing Workflow
1. **Symptom Assessment**:
Perform visual inspection
2. **Component Testing**:
Check voltage
3. **Component Installation**:
Follow torque specs
4. **Final Quality Check**:
Test drive vehicle
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## Critical Instruments
| **Tool Type** | **Examples** | **Purpose** |
|—|—|—|
| Code Reader | BlueDriver | Live data streaming |
| Mechanical Tools | Smoke machine | Component repair |
—
## Service Information References
### Auto Repair Source
– Capabilities:
TSB access [8]
Factory repair procedures
### Mobile Applications
– Vehicle Service App:
ECU pinouts [5]
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## Affordable Maintenance Advice
– Routine checkups extends vehicle life
– Master code scanning to avoid unnecessary repairs
– Select certified components when OEM prices prohibitive [7]